<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2026 Workiva-->
<!--r:019d2478-ba21-7c00-9e03-cefe2cfe4926,g:65aba69d-6001-4aa7-96b5-8c734d24a361-->
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/all" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member"/>
  <link:roleRef roleURI="http://www.exlservice.com/role/CONSOLIDATEDSTATEMENTSOFSTOCKHOLDERSEQUITYUNAUDITED" xlink:type="simple" xlink:href="exls-20260331.xsd#CONSOLIDATEDSTATEMENTSOFSTOCKHOLDERSEQUITYUNAUDITED"/>
  <link:definitionLink xlink:role="http://www.exlservice.com/role/CONSOLIDATEDSTATEMENTSOFSTOCKHOLDERSEQUITYUNAUDITED" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_019d2478-bbd5-790e-8efb-a09a6d65de12" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_019d2478-bbd5-74f3-8976-a39ae9738627" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_019d2478-bbd5-790e-8efb-a09a6d65de12" xlink:to="loc_us-gaap_StatementTable_019d2478-bbd5-74f3-8976-a39ae9738627" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_019d2478-bbd5-792e-8a70-c2f2faab9ca3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_019d2478-bbd5-74f3-8976-a39ae9738627" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_019d2478-bbd5-792e-8a70-c2f2faab9ca3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_019d2478-bbd5-792e-8a70-c2f2faab9ca3_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_019d2478-bbd5-792e-8a70-c2f2faab9ca3" xlink:to="loc_us-gaap_EquityComponentDomain_019d2478-bbd5-792e-8a70-c2f2faab9ca3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_019d2478-bbd5-7ffc-a2b7-a0ec497e9869" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_019d2478-bbd5-792e-8a70-c2f2faab9ca3" xlink:to="loc_us-gaap_EquityComponentDomain_019d2478-bbd5-7ffc-a2b7-a0ec497e9869" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockMember_019d2478-bbd5-75ef-85a8-489e1cac7131" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019d2478-bbd5-7ffc-a2b7-a0ec497e9869" xlink:to="loc_us-gaap_CommonStockMember_019d2478-bbd5-75ef-85a8-489e1cac7131" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalPaidInCapitalMember_019d2478-bbd5-7e85-849b-b3fc3cb9efb5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdditionalPaidInCapitalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019d2478-bbd5-7ffc-a2b7-a0ec497e9869" xlink:to="loc_us-gaap_AdditionalPaidInCapitalMember_019d2478-bbd5-7e85-849b-b3fc3cb9efb5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsMember_019d2478-bbd5-7d3e-9f83-0709ef6c80fc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RetainedEarningsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019d2478-bbd5-7ffc-a2b7-a0ec497e9869" xlink:to="loc_us-gaap_RetainedEarningsMember_019d2478-bbd5-7d3e-9f83-0709ef6c80fc" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_019d2478-bbd5-7e5e-9e7e-d2c272b056c7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019d2478-bbd5-7ffc-a2b7-a0ec497e9869" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_019d2478-bbd5-7e5e-9e7e-d2c272b056c7" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockCommonMember_019d2478-bbd5-7d29-9f45-d9330f43bbc7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TreasuryStockCommonMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019d2478-bbd5-7ffc-a2b7-a0ec497e9869" xlink:to="loc_us-gaap_TreasuryStockCommonMember_019d2478-bbd5-7d29-9f45-d9330f43bbc7" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramAxis_019d9120-e1b6-7dd5-b9c2-4e5716ea24f2" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ShareRepurchaseProgramAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_019d2478-bbd5-74f3-8976-a39ae9738627" xlink:to="loc_srt_ShareRepurchaseProgramAxis_019d9120-e1b6-7dd5-b9c2-4e5716ea24f2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramDomain_019d9120-e1b6-7dd5-b9c2-4e5716ea24f2_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ShareRepurchaseProgramDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ShareRepurchaseProgramAxis_019d9120-e1b6-7dd5-b9c2-4e5716ea24f2" xlink:to="loc_srt_ShareRepurchaseProgramDomain_019d9120-e1b6-7dd5-b9c2-4e5716ea24f2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramDomain_019d9120-e1b6-795b-bac2-7d57cb38e883" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ShareRepurchaseProgramDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ShareRepurchaseProgramAxis_019d9120-e1b6-7dd5-b9c2-4e5716ea24f2" xlink:to="loc_srt_ShareRepurchaseProgramDomain_019d9120-e1b6-795b-bac2-7d57cb38e883" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_AcceleratedShareRepurchaseAgreementASRAgreementMember_019d9121-0210-74f8-bced-b7a509ee2ff4" xlink:href="exls-20260331.xsd#exls_AcceleratedShareRepurchaseAgreementASRAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ShareRepurchaseProgramDomain_019d9120-e1b6-795b-bac2-7d57cb38e883" xlink:to="loc_exls_AcceleratedShareRepurchaseAgreementASRAgreementMember_019d9121-0210-74f8-bced-b7a509ee2ff4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019d2478-bbd5-796e-83cb-0a68d25fdfd9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInStockholdersEquityRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019d2478-bbd5-790e-8efb-a09a6d65de12" xlink:to="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019d2478-bbd5-796e-83cb-0a68d25fdfd9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_019d2478-bbd5-709b-a27d-a928625e67b9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019d2478-bbd5-796e-83cb-0a68d25fdfd9" xlink:to="loc_us-gaap_CommonStockSharesOutstanding_019d2478-bbd5-709b-a27d-a928625e67b9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_019d2478-bbd5-7b62-9f51-3616fe5fbcb0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019d2478-bbd5-796e-83cb-0a68d25fdfd9" xlink:to="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_019d2478-bbd5-7b62-9f51-3616fe5fbcb0" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockCommonShares_019d2478-bbd5-77f0-8ad6-566eeb6286de" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TreasuryStockCommonShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019d2478-bbd5-796e-83cb-0a68d25fdfd9" xlink:to="loc_us-gaap_TreasuryStockCommonShares_019d2478-bbd5-77f0-8ad6-566eeb6286de" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_019d2478-bbd5-7772-bb57-1fcb431c3ac4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019d2478-bbd5-796e-83cb-0a68d25fdfd9" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_019d2478-bbd5-7772-bb57-1fcb431c3ac4" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_019d2478-bbd5-77cf-9daa-24b21d496d92" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019d2478-bbd5-796e-83cb-0a68d25fdfd9" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_019d2478-bbd5-77cf-9daa-24b21d496d92" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_019d2478-bbd5-744f-ab25-149141794941" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019d2478-bbd5-796e-83cb-0a68d25fdfd9" xlink:to="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_019d2478-bbd5-744f-ab25-149141794941" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockSharesAcquired_019d2478-bbd5-7b2f-a053-6f94c2082b75" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TreasuryStockSharesAcquired"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019d2478-bbd5-796e-83cb-0a68d25fdfd9" xlink:to="loc_us-gaap_TreasuryStockSharesAcquired_019d2478-bbd5-7b2f-a053-6f94c2082b75" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockValueAcquiredCostMethod_019d2478-bbd5-7382-8476-1db0a9a95522" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TreasuryStockValueAcquiredCostMethod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019d2478-bbd5-796e-83cb-0a68d25fdfd9" xlink:to="loc_us-gaap_TreasuryStockValueAcquiredCostMethod_019d2478-bbd5-7382-8476-1db0a9a95522" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_AdjustmentsToAdditionalPaidInCapitalAcceleratedShareRepurchase_019d2478-bbd5-7f29-bbe8-59cae1ab4b9c" xlink:href="exls-20260331.xsd#exls_AdjustmentsToAdditionalPaidInCapitalAcceleratedShareRepurchase"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019d2478-bbd5-796e-83cb-0a68d25fdfd9" xlink:to="loc_exls_AdjustmentsToAdditionalPaidInCapitalAcceleratedShareRepurchase_019d2478-bbd5-7f29-bbe8-59cae1ab4b9c" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_ShareBasedPaymentArrangementValueSharesIssuedNetOfTaxWithholdings_019d2478-bbd5-7d62-be45-146c11be8a98" xlink:href="exls-20260331.xsd#exls_ShareBasedPaymentArrangementValueSharesIssuedNetOfTaxWithholdings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019d2478-bbd5-796e-83cb-0a68d25fdfd9" xlink:to="loc_exls_ShareBasedPaymentArrangementValueSharesIssuedNetOfTaxWithholdings_019d2478-bbd5-7d62-be45-146c11be8a98" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_019d2478-bbd5-73fd-a464-f6083ec58a34" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019d2478-bbd5-796e-83cb-0a68d25fdfd9" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_019d2478-bbd5-73fd-a464-f6083ec58a34" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_019d2478-bbd5-74ae-badd-b5dbee316311" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019d2478-bbd5-796e-83cb-0a68d25fdfd9" xlink:to="loc_us-gaap_NetIncomeLoss_019d2478-bbd5-74ae-badd-b5dbee316311" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_019d2478-bbd5-7f67-969c-7462a30b9e28" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesOutstanding"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_019d2478-bbd5-76da-a351-c6a2842d98b0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockCommonShares_019d2478-bbd5-7595-a508-2af13f744857" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TreasuryStockCommonShares"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.exlservice.com/role/SegmentInformationRevenuesandCostofRevenuesforCompanysReportableSegmentsDetails" xlink:type="simple" xlink:href="exls-20260331.xsd#SegmentInformationRevenuesandCostofRevenuesforCompanysReportableSegmentsDetails"/>
  <link:definitionLink xlink:role="http://www.exlservice.com/role/SegmentInformationRevenuesandCostofRevenuesforCompanysReportableSegmentsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems_019d2478-bbd5-7de0-9ece-8ef2fd39772f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable_019d2478-bbd5-7af1-ada2-53a35b531944" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems_019d2478-bbd5-7de0-9ece-8ef2fd39772f" xlink:to="loc_us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable_019d2478-bbd5-7af1-ada2-53a35b531944" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_019d2478-bbd5-7579-8ba2-7fa7cebbcac7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable_019d2478-bbd5-7af1-ada2-53a35b531944" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_019d2478-bbd5-7579-8ba2-7fa7cebbcac7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_019d2478-bbd5-7579-8ba2-7fa7cebbcac7_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_019d2478-bbd5-7579-8ba2-7fa7cebbcac7" xlink:to="loc_us-gaap_SegmentDomain_019d2478-bbd5-7579-8ba2-7fa7cebbcac7_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_019d2478-bbd5-78fd-968a-e10d3c41fa37" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_019d2478-bbd5-7579-8ba2-7fa7cebbcac7" xlink:to="loc_us-gaap_SegmentDomain_019d2478-bbd5-78fd-968a-e10d3c41fa37" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_InsuranceMember_019d2478-bbd5-7336-8f75-d68bab510853" xlink:href="exls-20260331.xsd#exls_InsuranceMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019d2478-bbd5-78fd-968a-e10d3c41fa37" xlink:to="loc_exls_InsuranceMember_019d2478-bbd5-7336-8f75-d68bab510853" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_HealthcareAndLifeSciencesMember_019d2478-bbd5-7956-83d9-81c7bc365d7c" xlink:href="exls-20260331.xsd#exls_HealthcareAndLifeSciencesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019d2478-bbd5-78fd-968a-e10d3c41fa37" xlink:to="loc_exls_HealthcareAndLifeSciencesMember_019d2478-bbd5-7956-83d9-81c7bc365d7c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_BankingCapitalMarketsAndDiversifiedIndustriesMember_019d2478-bbd5-7293-96aa-8799b43f3e95" xlink:href="exls-20260331.xsd#exls_BankingCapitalMarketsAndDiversifiedIndustriesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019d2478-bbd5-78fd-968a-e10d3c41fa37" xlink:to="loc_exls_BankingCapitalMarketsAndDiversifiedIndustriesMember_019d2478-bbd5-7293-96aa-8799b43f3e95" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_InternationalGrowthMarketsMember_019d2478-bbd5-76ea-98b0-11ebae1e2dbd" xlink:href="exls-20260331.xsd#exls_InternationalGrowthMarketsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019d2478-bbd5-78fd-968a-e10d3c41fa37" xlink:to="loc_exls_InternationalGrowthMarketsMember_019d2478-bbd5-76ea-98b0-11ebae1e2dbd" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_019d2478-bbd5-7c57-bb4d-d3d3daca90c9" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable_019d2478-bbd5-7af1-ada2-53a35b531944" xlink:to="loc_srt_ProductOrServiceAxis_019d2478-bbd5-7c57-bb4d-d3d3daca90c9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_019d2478-bbd5-7c57-bb4d-d3d3daca90c9_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_019d2478-bbd5-7c57-bb4d-d3d3daca90c9" xlink:to="loc_srt_ProductsAndServicesDomain_019d2478-bbd5-7c57-bb4d-d3d3daca90c9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_019d2478-bbd5-764f-9169-de0c7c4ec066" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_019d2478-bbd5-7c57-bb4d-d3d3daca90c9" xlink:to="loc_srt_ProductsAndServicesDomain_019d2478-bbd5-764f-9169-de0c7c4ec066" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_DataAndAILedServicesMember_019d2478-bbd5-72e1-86a5-c8f3c126624a" xlink:href="exls-20260331.xsd#exls_DataAndAILedServicesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_019d2478-bbd5-764f-9169-de0c7c4ec066" xlink:to="loc_exls_DataAndAILedServicesMember_019d2478-bbd5-72e1-86a5-c8f3c126624a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_DigitalOperationsServicesMember_019d2478-bbd5-77f8-a815-d76f6a49d6e4" xlink:href="exls-20260331.xsd#exls_DigitalOperationsServicesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_019d2478-bbd5-764f-9169-de0c7c4ec066" xlink:to="loc_exls_DigitalOperationsServicesMember_019d2478-bbd5-77f8-a815-d76f6a49d6e4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_019d2478-bbd5-7e70-a87e-c992c72ad1ce" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable_019d2478-bbd5-7af1-ada2-53a35b531944" xlink:to="loc_srt_StatementGeographicalAxis_019d2478-bbd5-7e70-a87e-c992c72ad1ce" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_019d2478-bbd5-7e70-a87e-c992c72ad1ce_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_019d2478-bbd5-7e70-a87e-c992c72ad1ce" xlink:to="loc_srt_SegmentGeographicalDomain_019d2478-bbd5-7e70-a87e-c992c72ad1ce_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_019d2478-bbd5-756c-8428-86dc1509f80e" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_019d2478-bbd5-7e70-a87e-c992c72ad1ce" xlink:to="loc_srt_SegmentGeographicalDomain_019d2478-bbd5-756c-8428-86dc1509f80e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_NorthAmericaMember_019d2478-bbd5-7a56-95ac-18301a4fd98a" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_NorthAmericaMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_019d2478-bbd5-756c-8428-86dc1509f80e" xlink:to="loc_srt_NorthAmericaMember_019d2478-bbd5-7a56-95ac-18301a4fd98a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_RestOfWorldMember_019d2478-bbd5-70cb-a3fd-997fa9fb4a69" xlink:href="exls-20260331.xsd#exls_RestOfWorldMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_019d2478-bbd5-756c-8428-86dc1509f80e" xlink:to="loc_exls_RestOfWorldMember_019d2478-bbd5-70cb-a3fd-997fa9fb4a69" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_019d2478-bbd5-7b4b-9e32-9f010ae737f4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems_019d2478-bbd5-7de0-9ece-8ef2fd39772f" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_019d2478-bbd5-7b4b-9e32-9f010ae737f4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostOfRevenueAbstract_019d2478-bbd5-7fa9-97ad-b6cbb347fcc2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CostOfRevenueAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems_019d2478-bbd5-7de0-9ece-8ef2fd39772f" xlink:to="loc_us-gaap_CostOfRevenueAbstract_019d2478-bbd5-7fa9-97ad-b6cbb347fcc2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostDirectLabor_019d2478-bbd5-72b0-9b21-36d4bb12f4c9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CostDirectLabor"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostOfRevenueAbstract_019d2478-bbd5-7fa9-97ad-b6cbb347fcc2" xlink:to="loc_us-gaap_CostDirectLabor_019d2478-bbd5-72b0-9b21-36d4bb12f4c9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DirectOperatingCosts_019d2478-bbd5-7776-b09e-4c70c904a15f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DirectOperatingCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostOfRevenueAbstract_019d2478-bbd5-7fa9-97ad-b6cbb347fcc2" xlink:to="loc_us-gaap_DirectOperatingCosts_019d2478-bbd5-7776-b09e-4c70c904a15f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCostOfOperatingRevenue_019d2478-bbd5-7174-9240-9a8afea519cb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherCostOfOperatingRevenue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostOfRevenueAbstract_019d2478-bbd5-7fa9-97ad-b6cbb347fcc2" xlink:to="loc_us-gaap_OtherCostOfOperatingRevenue_019d2478-bbd5-7174-9240-9a8afea519cb" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GrossProfit_019d2478-bbd5-7d9c-a353-dc1500f9f3f8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GrossProfit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems_019d2478-bbd5-7de0-9ece-8ef2fd39772f" xlink:to="loc_us-gaap_GrossProfit_019d2478-bbd5-7d9c-a353-dc1500f9f3f8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingExpenses_019d2478-bbd5-7adf-9115-727ca906d58c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingExpenses"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems_019d2478-bbd5-7de0-9ece-8ef2fd39772f" xlink:to="loc_us-gaap_OperatingExpenses_019d2478-bbd5-7adf-9115-727ca906d58c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingIncomeLoss_019d3eb4-49ce-7c21-93ac-34cd2f685733" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems_019d2478-bbd5-7de0-9ece-8ef2fd39772f" xlink:to="loc_us-gaap_OperatingIncomeLoss_019d3eb4-49ce-7c21-93ac-34cd2f685733" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NonoperatingIncomeExpense_019d2478-bbd5-756e-98cd-febffb7a250e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NonoperatingIncomeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems_019d2478-bbd5-7de0-9ece-8ef2fd39772f" xlink:to="loc_us-gaap_NonoperatingIncomeExpense_019d2478-bbd5-756e-98cd-febffb7a250e" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_019d3eb4-f1a4-748d-a97c-3b5d6529b378" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems_019d2478-bbd5-7de0-9ece-8ef2fd39772f" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_019d3eb4-f1a4-748d-a97c-3b5d6529b378" xlink:type="arc" order="6"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.exlservice.com/role/SegmentInformationRevenuesBasedonGeographicalInformationDetails" xlink:type="simple" xlink:href="exls-20260331.xsd#SegmentInformationRevenuesBasedonGeographicalInformationDetails"/>
  <link:definitionLink xlink:role="http://www.exlservice.com/role/SegmentInformationRevenuesBasedonGeographicalInformationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems_019d2478-bbd5-7070-ade7-992b1544b693" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_019d2478-bbd5-728a-8860-24ede12b6823" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems_019d2478-bbd5-7070-ade7-992b1544b693" xlink:to="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_019d2478-bbd5-728a-8860-24ede12b6823" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_019d2478-bbd5-71f3-9545-1243dc181d47" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_019d2478-bbd5-728a-8860-24ede12b6823" xlink:to="loc_srt_StatementGeographicalAxis_019d2478-bbd5-71f3-9545-1243dc181d47" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_019d2478-bbd5-71f3-9545-1243dc181d47_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_019d2478-bbd5-71f3-9545-1243dc181d47" xlink:to="loc_srt_SegmentGeographicalDomain_019d2478-bbd5-71f3-9545-1243dc181d47_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_019d2478-bbd5-777c-b2ac-8ca7339a01cd" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_019d2478-bbd5-71f3-9545-1243dc181d47" xlink:to="loc_srt_SegmentGeographicalDomain_019d2478-bbd5-777c-b2ac-8ca7339a01cd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_NorthAmericaMember_019d2478-bbd5-7f7c-bb99-c9754dd820d4" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_NorthAmericaMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_019d2478-bbd5-777c-b2ac-8ca7339a01cd" xlink:to="loc_srt_NorthAmericaMember_019d2478-bbd5-7f7c-bb99-c9754dd820d4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_TheUnitedKingdomAndEuropeMember_019d2478-bbd5-7698-a9e5-57a4746d8f63" xlink:href="exls-20260331.xsd#exls_TheUnitedKingdomAndEuropeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_019d2478-bbd5-777c-b2ac-8ca7339a01cd" xlink:to="loc_exls_TheUnitedKingdomAndEuropeMember_019d2478-bbd5-7698-a9e5-57a4746d8f63" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_RestOfWorldMember_019d2478-bbd5-77f1-b211-b675f0e7e4b8" xlink:href="exls-20260331.xsd#exls_RestOfWorldMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_019d2478-bbd5-777c-b2ac-8ca7339a01cd" xlink:to="loc_exls_RestOfWorldMember_019d2478-bbd5-77f1-b211-b675f0e7e4b8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_019d2478-bbd5-74dd-a7bd-fe57aa59ddac" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems_019d2478-bbd5-7070-ade7-992b1544b693" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_019d2478-bbd5-74dd-a7bd-fe57aa59ddac" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.exlservice.com/role/SegmentInformationRevenuesbyIndustryVerticalsDetails" xlink:type="simple" xlink:href="exls-20260331.xsd#SegmentInformationRevenuesbyIndustryVerticalsDetails"/>
  <link:definitionLink xlink:role="http://www.exlservice.com/role/SegmentInformationRevenuesbyIndustryVerticalsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems_019d3ebb-2c9c-7ac8-9184-ea1653721f6b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable_019d3ebb-2c9c-771c-a913-67e6f489aee9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems_019d3ebb-2c9c-7ac8-9184-ea1653721f6b" xlink:to="loc_us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable_019d3ebb-2c9c-771c-a913-67e6f489aee9" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_019d3ebb-2c9c-7531-ade2-c6e08d892e50" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable_019d3ebb-2c9c-771c-a913-67e6f489aee9" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_019d3ebb-2c9c-7531-ade2-c6e08d892e50" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_019d3ebb-2c9c-7531-ade2-c6e08d892e50_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_019d3ebb-2c9c-7531-ade2-c6e08d892e50" xlink:to="loc_us-gaap_SegmentDomain_019d3ebb-2c9c-7531-ade2-c6e08d892e50_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_019d3ebb-2c9c-79e4-b378-013c9cfe8a94" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_019d3ebb-2c9c-7531-ade2-c6e08d892e50" xlink:to="loc_us-gaap_SegmentDomain_019d3ebb-2c9c-79e4-b378-013c9cfe8a94" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_InsuranceMember_019d3ebb-2c9c-7e57-82e6-96f81ac08867" xlink:href="exls-20260331.xsd#exls_InsuranceMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019d3ebb-2c9c-79e4-b378-013c9cfe8a94" xlink:to="loc_exls_InsuranceMember_019d3ebb-2c9c-7e57-82e6-96f81ac08867" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_HealthcareAndLifeSciencesMember_019d3ebb-2c9c-73b1-80c8-07643abe2d8f" xlink:href="exls-20260331.xsd#exls_HealthcareAndLifeSciencesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019d3ebb-2c9c-79e4-b378-013c9cfe8a94" xlink:to="loc_exls_HealthcareAndLifeSciencesMember_019d3ebb-2c9c-73b1-80c8-07643abe2d8f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_BankingCapitalMarketsAndDiversifiedIndustriesMember_019d3ebb-2c9c-7b71-8b53-35fb02dde1ff" xlink:href="exls-20260331.xsd#exls_BankingCapitalMarketsAndDiversifiedIndustriesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019d3ebb-2c9c-79e4-b378-013c9cfe8a94" xlink:to="loc_exls_BankingCapitalMarketsAndDiversifiedIndustriesMember_019d3ebb-2c9c-7b71-8b53-35fb02dde1ff" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_019d3ebb-2c9c-783c-8bbe-b66e8be6aa0f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems_019d3ebb-2c9c-7ac8-9184-ea1653721f6b" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_019d3ebb-2c9c-783c-8bbe-b66e8be6aa0f" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.exlservice.com/role/SegmentInformationPropertyandEquipmentNetBasedonGeographicalInformationDetails" xlink:type="simple" xlink:href="exls-20260331.xsd#SegmentInformationPropertyandEquipmentNetBasedonGeographicalInformationDetails"/>
  <link:definitionLink xlink:role="http://www.exlservice.com/role/SegmentInformationPropertyandEquipmentNetBasedonGeographicalInformationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems_019d2478-bbd5-7bf5-8095-e30e9a5156e9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_019d2478-bbd5-7125-a9fa-e344576430f1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems_019d2478-bbd5-7bf5-8095-e30e9a5156e9" xlink:to="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_019d2478-bbd5-7125-a9fa-e344576430f1" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_019d2478-bbd5-78f8-95f6-c3cd31a22374" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_019d2478-bbd5-7125-a9fa-e344576430f1" xlink:to="loc_srt_StatementGeographicalAxis_019d2478-bbd5-78f8-95f6-c3cd31a22374" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_019d2478-bbd5-78f8-95f6-c3cd31a22374_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_019d2478-bbd5-78f8-95f6-c3cd31a22374" xlink:to="loc_srt_SegmentGeographicalDomain_019d2478-bbd5-78f8-95f6-c3cd31a22374_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_019d2478-bbd5-7e07-854f-cf3612f74e5b" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_019d2478-bbd5-78f8-95f6-c3cd31a22374" xlink:to="loc_srt_SegmentGeographicalDomain_019d2478-bbd5-7e07-854f-cf3612f74e5b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_IN_019d2478-bbd5-7336-9db2-03140c720ba6" xlink:href="https://xbrl.sec.gov/country/2025/country-2025.xsd#country_IN"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_019d2478-bbd5-7e07-854f-cf3612f74e5b" xlink:to="loc_country_IN_019d2478-bbd5-7336-9db2-03140c720ba6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_NorthAmericaMember_019d2478-bbd5-7225-96e4-3b010d70d2da" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_NorthAmericaMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_019d2478-bbd5-7e07-854f-cf3612f74e5b" xlink:to="loc_srt_NorthAmericaMember_019d2478-bbd5-7225-96e4-3b010d70d2da" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_PH_019d2478-bbd5-7cf5-ab27-92c87c2e5792" xlink:href="https://xbrl.sec.gov/country/2025/country-2025.xsd#country_PH"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_019d2478-bbd5-7e07-854f-cf3612f74e5b" xlink:to="loc_country_PH_019d2478-bbd5-7cf5-ab27-92c87c2e5792" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_ZA_019d2478-bbd5-7307-b3c5-2f9afe68c208" xlink:href="https://xbrl.sec.gov/country/2025/country-2025.xsd#country_ZA"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_019d2478-bbd5-7e07-854f-cf3612f74e5b" xlink:to="loc_country_ZA_019d2478-bbd5-7307-b3c5-2f9afe68c208" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_RestOfWorldMember_019d2478-bbd5-79f2-9895-7cc43f821993" xlink:href="exls-20260331.xsd#exls_RestOfWorldMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_019d2478-bbd5-7e07-854f-cf3612f74e5b" xlink:to="loc_exls_RestOfWorldMember_019d2478-bbd5-79f2-9895-7cc43f821993" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoncurrentAssets_019d2478-bbd5-79ad-a822-c03869459c7e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NoncurrentAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems_019d2478-bbd5-7bf5-8095-e30e9a5156e9" xlink:to="loc_us-gaap_NoncurrentAssets_019d2478-bbd5-79ad-a822-c03869459c7e" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.exlservice.com/role/RevenuesnetandAccountsReceivablenetAdditionalInformationDetails" xlink:type="simple" xlink:href="exls-20260331.xsd#RevenuesnetandAccountsReceivablenetAdditionalInformationDetails"/>
  <link:definitionLink xlink:role="http://www.exlservice.com/role/RevenuesnetandAccountsReceivablenetAdditionalInformationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedContractCostLineItems_019d2478-bbd5-7387-88d6-00fb37fde1f8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CapitalizedContractCostLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedContractCostTable_019d2478-bbd5-7d24-a415-da56331fa289" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CapitalizedContractCostTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_CapitalizedContractCostLineItems_019d2478-bbd5-7387-88d6-00fb37fde1f8" xlink:to="loc_us-gaap_CapitalizedContractCostTable_019d2478-bbd5-7d24-a415-da56331fa289" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedContractCostAxis_019d2478-bbd5-7ba1-a148-31880d48ab3a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CapitalizedContractCostAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_CapitalizedContractCostTable_019d2478-bbd5-7d24-a415-da56331fa289" xlink:to="loc_us-gaap_CapitalizedContractCostAxis_019d2478-bbd5-7ba1-a148-31880d48ab3a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedContractCostDomain_019d2478-bbd5-7ba1-a148-31880d48ab3a_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CapitalizedContractCostDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CapitalizedContractCostAxis_019d2478-bbd5-7ba1-a148-31880d48ab3a" xlink:to="loc_us-gaap_CapitalizedContractCostDomain_019d2478-bbd5-7ba1-a148-31880d48ab3a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedContractCostDomain_019d2478-bbd5-7537-b1d2-9e76d4401fff" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CapitalizedContractCostDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CapitalizedContractCostAxis_019d2478-bbd5-7ba1-a148-31880d48ab3a" xlink:to="loc_us-gaap_CapitalizedContractCostDomain_019d2478-bbd5-7537-b1d2-9e76d4401fff" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_ContractFulfillmentCostsMember_019d2478-bbd5-74f6-bd15-3dac9d5a5f5a" xlink:href="exls-20260331.xsd#exls_ContractFulfillmentCostsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CapitalizedContractCostDomain_019d2478-bbd5-7537-b1d2-9e76d4401fff" xlink:to="loc_exls_ContractFulfillmentCostsMember_019d2478-bbd5-74f6-bd15-3dac9d5a5f5a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_ContractAcquisitionCostsMember_019d2478-bbd5-7e59-8f55-981d72e17e54" xlink:href="exls-20260331.xsd#exls_ContractAcquisitionCostsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CapitalizedContractCostDomain_019d2478-bbd5-7537-b1d2-9e76d4401fff" xlink:to="loc_exls_ContractAcquisitionCostsMember_019d2478-bbd5-7e59-8f55-981d72e17e54" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnbilledContractsReceivable_019d2478-bbd5-782b-9c11-c2577156b4ef" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_UnbilledContractsReceivable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CapitalizedContractCostLineItems_019d2478-bbd5-7387-88d6-00fb37fde1f8" xlink:to="loc_us-gaap_UnbilledContractsReceivable_019d2478-bbd5-782b-9c11-c2577156b4ef" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_ContractWithCustomerAssetReceivablesFromPaymentIntegrityServices_019d2478-bbd5-7cb9-9662-40a4eea53f6d" xlink:href="exls-20260331.xsd#exls_ContractWithCustomerAssetReceivablesFromPaymentIntegrityServices"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CapitalizedContractCostLineItems_019d2478-bbd5-7387-88d6-00fb37fde1f8" xlink:to="loc_exls_ContractWithCustomerAssetReceivablesFromPaymentIntegrityServices_019d2478-bbd5-7cb9-9662-40a4eea53f6d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerAssetAccumulatedAllowanceForCreditLoss_019d2478-bbd5-7bc4-b3f9-daad2450af32" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ContractWithCustomerAssetAccumulatedAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CapitalizedContractCostLineItems_019d2478-bbd5-7387-88d6-00fb37fde1f8" xlink:to="loc_us-gaap_ContractWithCustomerAssetAccumulatedAllowanceForCreditLoss_019d2478-bbd5-7bc4-b3f9-daad2450af32" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedContractCostImpairmentLoss_019d2478-bbd5-7dc9-961a-199f02cd3fe3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CapitalizedContractCostImpairmentLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CapitalizedContractCostLineItems_019d2478-bbd5-7387-88d6-00fb37fde1f8" xlink:to="loc_us-gaap_CapitalizedContractCostImpairmentLoss_019d2478-bbd5-7dc9-961a-199f02cd3fe3" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.exlservice.com/role/RevenuesnetandAccountsReceivablenetContractAcquisitionandFulfillmentCostsDetails" xlink:type="simple" xlink:href="exls-20260331.xsd#RevenuesnetandAccountsReceivablenetContractAcquisitionandFulfillmentCostsDetails"/>
  <link:definitionLink xlink:role="http://www.exlservice.com/role/RevenuesnetandAccountsReceivablenetContractAcquisitionandFulfillmentCostsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedContractCostLineItems_019d2478-bbd5-7132-88b7-0a4be4adfce0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CapitalizedContractCostLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedContractCostTable_019d2478-bbd5-7b67-bc71-d12e923e3b3b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CapitalizedContractCostTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_CapitalizedContractCostLineItems_019d2478-bbd5-7132-88b7-0a4be4adfce0" xlink:to="loc_us-gaap_CapitalizedContractCostTable_019d2478-bbd5-7b67-bc71-d12e923e3b3b" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedContractCostAxis_019d2478-bbd5-7f28-94c6-6128a915369a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CapitalizedContractCostAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_CapitalizedContractCostTable_019d2478-bbd5-7b67-bc71-d12e923e3b3b" xlink:to="loc_us-gaap_CapitalizedContractCostAxis_019d2478-bbd5-7f28-94c6-6128a915369a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedContractCostDomain_019d2478-bbd5-7f28-94c6-6128a915369a_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CapitalizedContractCostDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CapitalizedContractCostAxis_019d2478-bbd5-7f28-94c6-6128a915369a" xlink:to="loc_us-gaap_CapitalizedContractCostDomain_019d2478-bbd5-7f28-94c6-6128a915369a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedContractCostDomain_019d2478-bbd5-750b-8a6e-72fd0941014b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CapitalizedContractCostDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CapitalizedContractCostAxis_019d2478-bbd5-7f28-94c6-6128a915369a" xlink:to="loc_us-gaap_CapitalizedContractCostDomain_019d2478-bbd5-750b-8a6e-72fd0941014b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_ContractAcquisitionCostsMember_019d2478-bbd5-7905-a0b5-6692082331a9" xlink:href="exls-20260331.xsd#exls_ContractAcquisitionCostsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CapitalizedContractCostDomain_019d2478-bbd5-750b-8a6e-72fd0941014b" xlink:to="loc_exls_ContractAcquisitionCostsMember_019d2478-bbd5-7905-a0b5-6692082331a9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_ContractFulfillmentCostsMember_019d2478-bbd5-70e4-8c55-fae7de700d1c" xlink:href="exls-20260331.xsd#exls_ContractFulfillmentCostsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CapitalizedContractCostDomain_019d2478-bbd5-750b-8a6e-72fd0941014b" xlink:to="loc_exls_ContractFulfillmentCostsMember_019d2478-bbd5-70e4-8c55-fae7de700d1c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_IncreaseDecreaseInCapitalizedContractCostsRollForward_019d2478-bbd5-7bc6-913e-038062185e23" xlink:href="exls-20260331.xsd#exls_IncreaseDecreaseInCapitalizedContractCostsRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CapitalizedContractCostLineItems_019d2478-bbd5-7132-88b7-0a4be4adfce0" xlink:to="loc_exls_IncreaseDecreaseInCapitalizedContractCostsRollForward_019d2478-bbd5-7bc6-913e-038062185e23" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedContractCostGross_019d2478-bbd5-70d2-a97d-af38d01ee78d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CapitalizedContractCostGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_exls_IncreaseDecreaseInCapitalizedContractCostsRollForward_019d2478-bbd5-7bc6-913e-038062185e23" xlink:to="loc_us-gaap_CapitalizedContractCostGross_019d2478-bbd5-70d2-a97d-af38d01ee78d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_IncreaseInCapitalizedContractCostGross_019d2478-bbd5-70d2-a317-f021287c8a88" xlink:href="exls-20260331.xsd#exls_IncreaseInCapitalizedContractCostGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_exls_IncreaseDecreaseInCapitalizedContractCostsRollForward_019d2478-bbd5-7bc6-913e-038062185e23" xlink:to="loc_exls_IncreaseInCapitalizedContractCostGross_019d2478-bbd5-70d2-a317-f021287c8a88" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedContractCostAmortization_019d2478-bbd5-7bd6-a9bf-13d71a11f354" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CapitalizedContractCostAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_exls_IncreaseDecreaseInCapitalizedContractCostsRollForward_019d2478-bbd5-7bc6-913e-038062185e23" xlink:to="loc_us-gaap_CapitalizedContractCostAmortization_019d2478-bbd5-7bd6-a9bf-13d71a11f354" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedContractCostGross_019d2478-bbd5-7e91-902b-e3059207c35e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CapitalizedContractCostGross"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.exlservice.com/role/EarningsPerShareAdditionalInformationDetails" xlink:type="simple" xlink:href="exls-20260331.xsd#EarningsPerShareAdditionalInformationDetails"/>
  <link:definitionLink xlink:role="http://www.exlservice.com/role/EarningsPerShareAdditionalInformationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_019d2478-bbd5-780d-a511-3034f37fce19" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_019d2478-bbd5-7308-a24e-d1b315b50708" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_019d2478-bbd5-780d-a511-3034f37fce19" xlink:to="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_019d2478-bbd5-7308-a24e-d1b315b50708" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramAxis_019d3ec3-8599-7d40-b082-12a6f915fa81" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ShareRepurchaseProgramAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_019d2478-bbd5-7308-a24e-d1b315b50708" xlink:to="loc_srt_ShareRepurchaseProgramAxis_019d3ec3-8599-7d40-b082-12a6f915fa81" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramDomain_019d3ec3-8599-7d40-b082-12a6f915fa81_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ShareRepurchaseProgramDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ShareRepurchaseProgramAxis_019d3ec3-8599-7d40-b082-12a6f915fa81" xlink:to="loc_srt_ShareRepurchaseProgramDomain_019d3ec3-8599-7d40-b082-12a6f915fa81_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramDomain_019d3ec3-8599-79b1-8f71-aefed89f6789" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ShareRepurchaseProgramDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ShareRepurchaseProgramAxis_019d3ec3-8599-7d40-b082-12a6f915fa81" xlink:to="loc_srt_ShareRepurchaseProgramDomain_019d3ec3-8599-79b1-8f71-aefed89f6789" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_A2026AcceleratedShareRepurchaseAgreementASRAgreementMember_019d3ec3-c86c-7f56-a5c5-2e506acf324d" xlink:href="exls-20260331.xsd#exls_A2026AcceleratedShareRepurchaseAgreementASRAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ShareRepurchaseProgramDomain_019d3ec3-8599-79b1-8f71-aefed89f6789" xlink:to="loc_exls_A2026AcceleratedShareRepurchaseAgreementASRAgreementMember_019d3ec3-c86c-7f56-a5c5-2e506acf324d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalPaidInCapital_019d3ec3-42c0-7788-b9ce-54ec4640385e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdditionalPaidInCapital"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_019d2478-bbd5-780d-a511-3034f37fce19" xlink:to="loc_us-gaap_AdditionalPaidInCapital_019d3ec3-42c0-7788-b9ce-54ec4640385e" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.exlservice.com/role/GoodwillandOtherIntangibleAssetsSummaryofGoodwillDetails" xlink:type="simple" xlink:href="exls-20260331.xsd#GoodwillandOtherIntangibleAssetsSummaryofGoodwillDetails"/>
  <link:definitionLink xlink:role="http://www.exlservice.com/role/GoodwillandOtherIntangibleAssetsSummaryofGoodwillDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillLineItems_019d2478-bbd5-710b-88e5-b10adb586882" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GoodwillLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfGoodwillTable_019d2478-bbd5-7c25-8cfe-58ef43fda19f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfGoodwillTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_GoodwillLineItems_019d2478-bbd5-710b-88e5-b10adb586882" xlink:to="loc_us-gaap_ScheduleOfGoodwillTable_019d2478-bbd5-7c25-8cfe-58ef43fda19f" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_019d2478-bbd5-7b90-ad5c-1247ae085e3a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfGoodwillTable_019d2478-bbd5-7c25-8cfe-58ef43fda19f" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_019d2478-bbd5-7b90-ad5c-1247ae085e3a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_019d2478-bbd5-7b90-ad5c-1247ae085e3a_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_019d2478-bbd5-7b90-ad5c-1247ae085e3a" xlink:to="loc_us-gaap_SegmentDomain_019d2478-bbd5-7b90-ad5c-1247ae085e3a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_019d2478-bbd5-74e8-afd2-3f26dac8513c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_019d2478-bbd5-7b90-ad5c-1247ae085e3a" xlink:to="loc_us-gaap_SegmentDomain_019d2478-bbd5-74e8-afd2-3f26dac8513c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_InsuranceMember_019d2478-bbd5-7c7c-a144-725897aa2d8b" xlink:href="exls-20260331.xsd#exls_InsuranceMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019d2478-bbd5-74e8-afd2-3f26dac8513c" xlink:to="loc_exls_InsuranceMember_019d2478-bbd5-7c7c-a144-725897aa2d8b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_HealthcareAndLifeSciencesMember_019d2478-bbd5-76d5-b0f7-5d68bdc4dba4" xlink:href="exls-20260331.xsd#exls_HealthcareAndLifeSciencesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019d2478-bbd5-74e8-afd2-3f26dac8513c" xlink:to="loc_exls_HealthcareAndLifeSciencesMember_019d2478-bbd5-76d5-b0f7-5d68bdc4dba4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_BankingCapitalMarketsAndDiversifiedIndustriesMember_019d2478-bbd5-7f52-8d30-66d8aff63104" xlink:href="exls-20260331.xsd#exls_BankingCapitalMarketsAndDiversifiedIndustriesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019d2478-bbd5-74e8-afd2-3f26dac8513c" xlink:to="loc_exls_BankingCapitalMarketsAndDiversifiedIndustriesMember_019d2478-bbd5-7f52-8d30-66d8aff63104" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_InternationalGrowthMarketsMember_019d2478-bbd5-766a-a9a6-a43886a54fbf" xlink:href="exls-20260331.xsd#exls_InternationalGrowthMarketsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019d2478-bbd5-74e8-afd2-3f26dac8513c" xlink:to="loc_exls_InternationalGrowthMarketsMember_019d2478-bbd5-766a-a9a6-a43886a54fbf" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillRollForward_019d2478-bbd5-7bcd-9984-6ceab5b320c9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GoodwillRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillLineItems_019d2478-bbd5-710b-88e5-b10adb586882" xlink:to="loc_us-gaap_GoodwillRollForward_019d2478-bbd5-7bcd-9984-6ceab5b320c9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Goodwill_019d2478-bbd5-75e9-bb95-272c013245c8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Goodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillRollForward_019d2478-bbd5-7bcd-9984-6ceab5b320c9" xlink:to="loc_us-gaap_Goodwill_019d2478-bbd5-75e9-bb95-272c013245c8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillForeignCurrencyTranslationGainLoss_019d2478-bbd5-7dba-9477-69590935b95f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GoodwillForeignCurrencyTranslationGainLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillRollForward_019d2478-bbd5-7bcd-9984-6ceab5b320c9" xlink:to="loc_us-gaap_GoodwillForeignCurrencyTranslationGainLoss_019d2478-bbd5-7dba-9477-69590935b95f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Goodwill_019d2478-bbd5-75ae-9a36-95b307c43ca6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Goodwill"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.exlservice.com/role/GoodwillandOtherIntangibleAssetsSummaryofIntangibleAssetsDetails" xlink:type="simple" xlink:href="exls-20260331.xsd#GoodwillandOtherIntangibleAssetsSummaryofIntangibleAssetsDetails"/>
  <link:definitionLink xlink:role="http://www.exlservice.com/role/GoodwillandOtherIntangibleAssetsSummaryofIntangibleAssetsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_019d2478-bbd5-7f91-a38a-3c12784f0900" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_019d2478-bbd5-7c20-aa9d-98bdaf7dca95" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_019d2478-bbd5-7f91-a38a-3c12784f0900" xlink:to="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_019d2478-bbd5-7c20-aa9d-98bdaf7dca95" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_019d2478-bbd5-7675-a8b4-39e58f42e7a1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_019d2478-bbd5-7c20-aa9d-98bdaf7dca95" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_019d2478-bbd5-7675-a8b4-39e58f42e7a1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019d2478-bbd5-7675-a8b4-39e58f42e7a1_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_019d2478-bbd5-7675-a8b4-39e58f42e7a1" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019d2478-bbd5-7675-a8b4-39e58f42e7a1_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019d2478-bbd5-7c6e-acce-03223816de82" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_019d2478-bbd5-7675-a8b4-39e58f42e7a1" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019d2478-bbd5-7c6e-acce-03223816de82" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CustomerRelationshipsMember_019d2478-bbd5-7521-90d2-072af819c800" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CustomerRelationshipsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019d2478-bbd5-7c6e-acce-03223816de82" xlink:to="loc_us-gaap_CustomerRelationshipsMember_019d2478-bbd5-7521-90d2-072af819c800" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DevelopedTechnologyRightsMember_019d2478-bbd5-722d-a986-ab18393ab9fa" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DevelopedTechnologyRightsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019d2478-bbd5-7c6e-acce-03223816de82" xlink:to="loc_us-gaap_DevelopedTechnologyRightsMember_019d2478-bbd5-722d-a986-ab18393ab9fa" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TrademarksAndTradeNamesMember_019d2478-bbd5-73d9-b57c-0fab3019f00c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TrademarksAndTradeNamesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019d2478-bbd5-7c6e-acce-03223816de82" xlink:to="loc_us-gaap_TrademarksAndTradeNamesMember_019d2478-bbd5-73d9-b57c-0fab3019f00c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoncompeteAgreementsMember_019d2478-bbd5-79ce-a186-b208fe3d01e8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NoncompeteAgreementsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019d2478-bbd5-7c6e-acce-03223816de82" xlink:to="loc_us-gaap_NoncompeteAgreementsMember_019d2478-bbd5-79ce-a186-b208fe3d01e8" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis_019d2478-bbd5-73f6-9fb8-659183c53857" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_019d2478-bbd5-7c20-aa9d-98bdaf7dca95" xlink:to="loc_us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis_019d2478-bbd5-73f6-9fb8-659183c53857" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain_019d2478-bbd5-73f6-9fb8-659183c53857_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis_019d2478-bbd5-73f6-9fb8-659183c53857" xlink:to="loc_us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain_019d2478-bbd5-73f6-9fb8-659183c53857_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain_019d2478-bbd5-729d-88d2-5a8d402def96" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis_019d2478-bbd5-73f6-9fb8-659183c53857" xlink:to="loc_us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain_019d2478-bbd5-729d-88d2-5a8d402def96" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TrademarksAndTradeNamesMember_019d2478-bbd5-79f4-af74-0ff89243d23b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TrademarksAndTradeNamesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain_019d2478-bbd5-729d-88d2-5a8d402def96" xlink:to="loc_us-gaap_TrademarksAndTradeNamesMember_019d2478-bbd5-79f4-af74-0ff89243d23b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsGross_019d2478-bbd5-76d3-9d0f-1775531cf1ec" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_019d2478-bbd5-7f91-a38a-3c12784f0900" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsGross_019d2478-bbd5-76d3-9d0f-1775531cf1ec" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_019d2478-bbd5-7b48-aae2-2f2427ce4ae1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_019d2478-bbd5-7f91-a38a-3c12784f0900" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_019d2478-bbd5-7b48-aae2-2f2427ce4ae1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsNet_019d2478-bbd5-7f72-af1d-cb48a32a0b79" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_019d2478-bbd5-7f91-a38a-3c12784f0900" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsNet_019d2478-bbd5-7f72-af1d-cb48a32a0b79" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_IndefiniteLivedIntangibleAssetsAbstract_019d2478-bbd5-7ee0-a094-2a58c6f803bf" xlink:href="exls-20260331.xsd#exls_IndefiniteLivedIntangibleAssetsAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_019d2478-bbd5-7f91-a38a-3c12784f0900" xlink:to="loc_exls_IndefiniteLivedIntangibleAssetsAbstract_019d2478-bbd5-7ee0-a094-2a58c6f803bf" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_019d2478-bbd5-7b95-ada0-61e2ec968704" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_exls_IndefiniteLivedIntangibleAssetsAbstract_019d2478-bbd5-7ee0-a094-2a58c6f803bf" xlink:to="loc_us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_019d2478-bbd5-7b95-ada0-61e2ec968704" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IntangibleAssetsGrossExcludingGoodwill_019d2478-bbd5-7056-9aa7-0438a810b678" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IntangibleAssetsGrossExcludingGoodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_019d2478-bbd5-7f91-a38a-3c12784f0900" xlink:to="loc_us-gaap_IntangibleAssetsGrossExcludingGoodwill_019d2478-bbd5-7056-9aa7-0438a810b678" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_019d2478-bbd5-7ae4-afa1-81c13ca72f3c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IntangibleAssetsNetExcludingGoodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_019d2478-bbd5-7f91-a38a-3c12784f0900" xlink:to="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_019d2478-bbd5-7ae4-afa1-81c13ca72f3c" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.exlservice.com/role/AccumulatedOtherComprehensiveIncomeLossDetails" xlink:type="simple" xlink:href="exls-20260331.xsd#AccumulatedOtherComprehensiveIncomeLossDetails"/>
  <link:definitionLink xlink:role="http://www.exlservice.com/role/AccumulatedOtherComprehensiveIncomeLossDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_019d2478-bca9-751c-a643-f4b765b61d0f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_019d2478-bca9-7361-a5c3-924a566cbf2d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_019d2478-bca9-751c-a643-f4b765b61d0f" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_019d2478-bca9-7361-a5c3-924a566cbf2d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_019d2478-bca9-7b61-9568-b498b9d033a9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_019d2478-bca9-7361-a5c3-924a566cbf2d" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_019d2478-bca9-7b61-9568-b498b9d033a9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_019d2478-bca9-7b61-9568-b498b9d033a9_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_019d2478-bca9-7b61-9568-b498b9d033a9" xlink:to="loc_us-gaap_EquityComponentDomain_019d2478-bca9-7b61-9568-b498b9d033a9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_019d2478-bca9-71f3-b543-01d2a96b8591" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_019d2478-bca9-7b61-9568-b498b9d033a9" xlink:to="loc_us-gaap_EquityComponentDomain_019d2478-bca9-71f3-b543-01d2a96b8591" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_019d2478-bca9-7d50-8bde-fcfa88d07dab" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019d2478-bca9-71f3-b543-01d2a96b8591" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_019d2478-bca9-7d50-8bde-fcfa88d07dab" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedTranslationAdjustmentMember_019d2478-bca9-780e-8e02-35d027d5bdf4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccumulatedTranslationAdjustmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_019d2478-bca9-7d50-8bde-fcfa88d07dab" xlink:to="loc_us-gaap_AccumulatedTranslationAdjustmentMember_019d2478-bca9-780e-8e02-35d027d5bdf4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedGainLossNetCashFlowHedgeParentMember_019d2478-bca9-7ab8-8ee4-e38a9195a766" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccumulatedGainLossNetCashFlowHedgeParentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_019d2478-bca9-7d50-8bde-fcfa88d07dab" xlink:to="loc_us-gaap_AccumulatedGainLossNetCashFlowHedgeParentMember_019d2478-bca9-7ab8-8ee4-e38a9195a766" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember_019d2478-bca9-7bd2-a9af-a0569da121c7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_019d2478-bca9-7d50-8bde-fcfa88d07dab" xlink:to="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember_019d2478-bca9-7bd2-a9af-a0569da121c7" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_019d2478-bca9-7412-bcca-4467c0eaf077" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AOCIAttributableToParentNetOfTaxRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_019d2478-bca9-751c-a643-f4b765b61d0f" xlink:to="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_019d2478-bca9-7412-bcca-4467c0eaf077" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_019d2478-bca9-72fe-8cd0-867b6546be74" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_019d2478-bca9-7412-bcca-4467c0eaf077" xlink:to="loc_us-gaap_StockholdersEquity_019d2478-bca9-72fe-8cd0-867b6546be74" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OciBeforeReclassificationsBeforeTaxAttributableToParent_019d2478-bca9-7819-8678-60ca9bf2a0c3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OciBeforeReclassificationsBeforeTaxAttributableToParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_019d2478-bca9-7412-bcca-4467c0eaf077" xlink:to="loc_us-gaap_OciBeforeReclassificationsBeforeTaxAttributableToParent_019d2478-bca9-7819-8678-60ca9bf2a0c3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationFromAociCurrentPeriodBeforeTaxAttributableToParent_019d2478-bca9-741a-a52d-59fb5ca395f2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ReclassificationFromAociCurrentPeriodBeforeTaxAttributableToParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_019d2478-bca9-7412-bcca-4467c0eaf077" xlink:to="loc_us-gaap_ReclassificationFromAociCurrentPeriodBeforeTaxAttributableToParent_019d2478-bca9-741a-a52d-59fb5ca395f2" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossTax_019d2478-bca9-7e8c-99de-060ff4eea9f1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherComprehensiveIncomeLossTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_019d2478-bca9-7412-bcca-4467c0eaf077" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossTax_019d2478-bca9-7e8c-99de-060ff4eea9f1" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_019d2478-bca9-7732-9f81-0b9bedaead7d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquity"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.exlservice.com/role/FairValueMeasurementsAssetsandLiabilitiesMeasuredatFairValueDetails" xlink:type="simple" xlink:href="exls-20260331.xsd#FairValueMeasurementsAssetsandLiabilitiesMeasuredatFairValueDetails"/>
  <link:definitionLink xlink:role="http://www.exlservice.com/role/FairValueMeasurementsAssetsandLiabilitiesMeasuredatFairValueDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019d2478-bcaa-7e0b-b982-a05f0833b79c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019d2478-bca9-73b8-a266-abe1f952139e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019d2478-bcaa-7e0b-b982-a05f0833b79c" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019d2478-bca9-73b8-a266-abe1f952139e" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019d2478-bca9-7955-b2b0-67c18cfbf81c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019d2478-bca9-73b8-a266-abe1f952139e" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019d2478-bca9-7955-b2b0-67c18cfbf81c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019d2478-bca9-7955-b2b0-67c18cfbf81c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019d2478-bca9-7955-b2b0-67c18cfbf81c" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019d2478-bca9-7955-b2b0-67c18cfbf81c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019d2478-bca9-7f54-a098-d8c263945178" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019d2478-bca9-7955-b2b0-67c18cfbf81c" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019d2478-bca9-7f54-a098-d8c263945178" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel1Member_019d2478-bca9-7a6a-90a4-fb24de204478" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueInputsLevel1Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019d2478-bca9-7f54-a098-d8c263945178" xlink:to="loc_us-gaap_FairValueInputsLevel1Member_019d2478-bca9-7a6a-90a4-fb24de204478" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel2Member_019d2478-bca9-7c0e-8418-06c069ea1ae9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueInputsLevel2Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019d2478-bca9-7f54-a098-d8c263945178" xlink:to="loc_us-gaap_FairValueInputsLevel2Member_019d2478-bca9-7c0e-8418-06c069ea1ae9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel3Member_019d2478-bcaa-71e9-9375-b34e186a073b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueInputsLevel3Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019d2478-bca9-7f54-a098-d8c263945178" xlink:to="loc_us-gaap_FairValueInputsLevel3Member_019d2478-bcaa-71e9-9375-b34e186a073b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsAxis_019d3efc-6642-7cdd-a5de-3a4354d94efb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashAndCashEquivalentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019d2478-bca9-73b8-a266-abe1f952139e" xlink:to="loc_us-gaap_CashAndCashEquivalentsAxis_019d3efc-6642-7cdd-a5de-3a4354d94efb" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_019d3efc-6642-7cdd-a5de-3a4354d94efb_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CashAndCashEquivalentsAxis_019d3efc-6642-7cdd-a5de-3a4354d94efb" xlink:to="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_019d3efc-6642-7cdd-a5de-3a4354d94efb_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_019d3efc-6642-7b6b-9d10-ee9a18c69e3a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CashAndCashEquivalentsAxis_019d3efc-6642-7cdd-a5de-3a4354d94efb" xlink:to="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_019d3efc-6642-7b6b-9d10-ee9a18c69e3a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MoneyMarketFundsMember_019d3efc-8afe-7295-96c5-10567ee2ee69" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MoneyMarketFundsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_019d3efc-6642-7b6b-9d10-ee9a18c69e3a" xlink:to="loc_us-gaap_MoneyMarketFundsMember_019d3efc-8afe-7295-96c5-10567ee2ee69" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_019d3efd-05cb-7aba-aac4-8c102d847721" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019d2478-bca9-73b8-a266-abe1f952139e" xlink:to="loc_us-gaap_FinancialInstrumentAxis_019d3efd-05cb-7aba-aac4-8c102d847721" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019d3efd-05cb-7aba-aac4-8c102d847721_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019d3efd-05cb-7aba-aac4-8c102d847721" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019d3efd-05cb-7aba-aac4-8c102d847721_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019d3efd-05cb-72db-96c7-8313f7e7d8c5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019d3efd-05cb-7aba-aac4-8c102d847721" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019d3efd-05cb-72db-96c7-8313f7e7d8c5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityFundsMember_019d3efd-3890-75b9-b1ed-affba2ef7307" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityFundsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019d3efd-05cb-72db-96c7-8313f7e7d8c5" xlink:to="loc_us-gaap_EquityFundsMember_019d3efd-3890-75b9-b1ed-affba2ef7307" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsFairValueDisclosureAbstract_019d2478-bcaa-7a7d-848a-c8fba78edba6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetsFairValueDisclosureAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019d2478-bcaa-7e0b-b982-a05f0833b79c" xlink:to="loc_us-gaap_AssetsFairValueDisclosureAbstract_019d2478-bcaa-7a7d-848a-c8fba78edba6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsFairValueDisclosure_019d2478-bcaa-78f4-b235-97f8d77e9377" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashAndCashEquivalentsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_019d2478-bcaa-7a7d-848a-c8fba78edba6" xlink:to="loc_us-gaap_CashAndCashEquivalentsFairValueDisclosure_019d2478-bcaa-78f4-b235-97f8d77e9377" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentsFairValueDisclosure_019d3efc-dcfd-70e0-ab64-3db95382b7c9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InvestmentsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_019d2478-bcaa-7a7d-848a-c8fba78edba6" xlink:to="loc_us-gaap_InvestmentsFairValueDisclosure_019d3efc-dcfd-70e0-ab64-3db95382b7c9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssets_019d3efd-8bca-77f8-b1c6-cb5d0d9e2768" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_019d2478-bcaa-7a7d-848a-c8fba78edba6" xlink:to="loc_us-gaap_DerivativeAssets_019d3efd-8bca-77f8-b1c6-cb5d0d9e2768" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsFairValueDisclosure_019d2478-bcaa-77b4-b218-4132b0a49844" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_019d2478-bcaa-7a7d-848a-c8fba78edba6" xlink:to="loc_us-gaap_AssetsFairValueDisclosure_019d2478-bcaa-77b4-b218-4132b0a49844" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_019d2478-bcaa-7d6d-89ca-bcc8d609698d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesFairValueDisclosureAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019d2478-bcaa-7e0b-b982-a05f0833b79c" xlink:to="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_019d2478-bcaa-7d6d-89ca-bcc8d609698d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilities_019d3f00-f8a6-77ff-a8e3-36a3c442647e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_019d2478-bcaa-7d6d-89ca-bcc8d609698d" xlink:to="loc_us-gaap_DerivativeLiabilities_019d3f00-f8a6-77ff-a8e3-36a3c442647e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationContingentConsiderationLiability_019d2478-bcaa-7ffe-ac06-33e32aa0fa0e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationContingentConsiderationLiability"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_019d2478-bcaa-7d6d-89ca-bcc8d609698d" xlink:to="loc_us-gaap_BusinessCombinationContingentConsiderationLiability_019d2478-bcaa-7ffe-ac06-33e32aa0fa0e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesFairValueDisclosure_019d2478-bcaa-78f3-97e5-9eef6f61adc5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_019d2478-bcaa-7d6d-89ca-bcc8d609698d" xlink:to="loc_us-gaap_LiabilitiesFairValueDisclosure_019d2478-bcaa-78f3-97e5-9eef6f61adc5" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.exlservice.com/role/FairValueMeasurementsChangesinthefairvalueofcontingentconsiderationDetails" xlink:type="simple" xlink:href="exls-20260331.xsd#FairValueMeasurementsChangesinthefairvalueofcontingentconsiderationDetails"/>
  <link:definitionLink xlink:role="http://www.exlservice.com/role/FairValueMeasurementsChangesinthefairvalueofcontingentconsiderationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019d2478-bcaa-738f-94d9-2d4d40966d9b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019d2478-bcaa-7420-a205-dafc6dba992f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019d2478-bcaa-738f-94d9-2d4d40966d9b" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019d2478-bcaa-7420-a205-dafc6dba992f" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByLiabilityClassAxis_019d2478-bcaa-7d49-a032-dfcc975ad80d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueByLiabilityClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019d2478-bcaa-7420-a205-dafc6dba992f" xlink:to="loc_us-gaap_FairValueByLiabilityClassAxis_019d2478-bcaa-7d49-a032-dfcc975ad80d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_019d2478-bcaa-7d49-a032-dfcc975ad80d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByLiabilityClassAxis_019d2478-bcaa-7d49-a032-dfcc975ad80d" xlink:to="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_019d2478-bcaa-7d49-a032-dfcc975ad80d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_019d2478-bcaa-7c03-802d-d03aacfc4bac" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByLiabilityClassAxis_019d2478-bcaa-7d49-a032-dfcc975ad80d" xlink:to="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_019d2478-bcaa-7c03-802d-d03aacfc4bac" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_ContingentConsiderationMember_019d2478-bcaa-75e4-b397-4781973bb5f2" xlink:href="exls-20260331.xsd#exls_ContingentConsiderationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_019d2478-bcaa-7c03-802d-d03aacfc4bac" xlink:to="loc_exls_ContingentConsiderationMember_019d2478-bcaa-75e4-b397-4781973bb5f2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019d3f07-ac02-7ef2-9a2b-b389b48be7cf" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019d2478-bcaa-738f-94d9-2d4d40966d9b" xlink:to="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019d3f07-ac02-7ef2-9a2b-b389b48be7cf" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue_019d2478-bcaa-7980-8c60-7b6bb1ae9032" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019d3f07-ac02-7ef2-9a2b-b389b48be7cf" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue_019d2478-bcaa-7980-8c60-7b6bb1ae9032" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings_019d2478-bcaa-758d-81e6-c7f798e0bff1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019d3f07-ac02-7ef2-9a2b-b389b48be7cf" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings_019d2478-bcaa-758d-81e6-c7f798e0bff1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements_019d2478-bcaa-7dc1-8ab2-af36228c6ee3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019d3f07-ac02-7ef2-9a2b-b389b48be7cf" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements_019d2478-bcaa-7dc1-8ab2-af36228c6ee3" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue_019d2478-bcaa-75db-84fb-2aa6218fbbca" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.exlservice.com/role/DerivativesandHedgeAccountingDerivativesincashflowhedgingDetails" xlink:type="simple" xlink:href="exls-20260331.xsd#DerivativesandHedgeAccountingDerivativesincashflowhedgingDetails"/>
  <link:definitionLink xlink:role="http://www.exlservice.com/role/DerivativesandHedgeAccountingDerivativesincashflowhedgingDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLineItems_019d2478-bcaa-7926-adb0-3559769909cd" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeTable_019d2478-bcaa-77be-9eea-3293110c165a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeLineItems_019d2478-bcaa-7926-adb0-3559769909cd" xlink:to="loc_us-gaap_DerivativeTable_019d2478-bcaa-77be-9eea-3293110c165a" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_019d2478-bcaa-7cb0-b8b7-3fc500577ed9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_019d2478-bcaa-77be-9eea-3293110c165a" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_019d2478-bcaa-7cb0-b8b7-3fc500577ed9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019d2478-bcaa-7cb0-b8b7-3fc500577ed9_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019d2478-bcaa-7cb0-b8b7-3fc500577ed9" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019d2478-bcaa-7cb0-b8b7-3fc500577ed9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019d2478-bcaa-7f2a-9e55-637120ebd265" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019d2478-bcaa-7cb0-b8b7-3fc500577ed9" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019d2478-bcaa-7f2a-9e55-637120ebd265" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignExchangeContractMember_019d2478-bcaa-7dbb-849f-1cdffd6397b9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ForeignExchangeContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019d2478-bcaa-7f2a-9e55-637120ebd265" xlink:to="loc_us-gaap_ForeignExchangeContractMember_019d2478-bcaa-7dbb-849f-1cdffd6397b9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019d2478-bcaa-7082-b1ab-ea811fef0923" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_019d2478-bcaa-77be-9eea-3293110c165a" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019d2478-bcaa-7082-b1ab-ea811fef0923" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingRelationshipDomain_019d2478-bcaa-7082-b1ab-ea811fef0923_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_HedgingRelationshipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019d2478-bcaa-7082-b1ab-ea811fef0923" xlink:to="loc_us-gaap_HedgingRelationshipDomain_019d2478-bcaa-7082-b1ab-ea811fef0923_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingRelationshipDomain_019d2478-bcaa-74e8-acd7-5e41ffaef179" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_HedgingRelationshipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019d2478-bcaa-7082-b1ab-ea811fef0923" xlink:to="loc_us-gaap_HedgingRelationshipDomain_019d2478-bcaa-74e8-acd7-5e41ffaef179" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashFlowHedgingMember_019d2478-bcaa-7b32-acc6-8164d0c0747d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashFlowHedgingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingRelationshipDomain_019d2478-bcaa-74e8-acd7-5e41ffaef179" xlink:to="loc_us-gaap_CashFlowHedgingMember_019d2478-bcaa-7b32-acc6-8164d0c0747d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationAxis_019d2478-bcaa-7dc2-9cde-d17bb28a7ed9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_HedgingDesignationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_019d2478-bcaa-77be-9eea-3293110c165a" xlink:to="loc_us-gaap_HedgingDesignationAxis_019d2478-bcaa-7dc2-9cde-d17bb28a7ed9" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain_019d2478-bcaa-7dc2-9cde-d17bb28a7ed9_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_HedgingDesignationAxis_019d2478-bcaa-7dc2-9cde-d17bb28a7ed9" xlink:to="loc_us-gaap_HedgingDesignationDomain_019d2478-bcaa-7dc2-9cde-d17bb28a7ed9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain_019d2478-bcaa-739f-8dc5-312e2303b2cc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_HedgingDesignationAxis_019d2478-bcaa-7dc2-9cde-d17bb28a7ed9" xlink:to="loc_us-gaap_HedgingDesignationDomain_019d2478-bcaa-739f-8dc5-312e2303b2cc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DesignatedAsHedgingInstrumentMember_019d2478-bcaa-793f-bee4-80171ec1bbc9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DesignatedAsHedgingInstrumentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingDesignationDomain_019d2478-bcaa-739f-8dc5-312e2303b2cc" xlink:to="loc_us-gaap_DesignatedAsHedgingInstrumentMember_019d2478-bcaa-793f-bee4-80171ec1bbc9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PositionAxis_019d2478-bcaa-7750-95b4-5248684bf050" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PositionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_019d2478-bcaa-77be-9eea-3293110c165a" xlink:to="loc_us-gaap_PositionAxis_019d2478-bcaa-7750-95b4-5248684bf050" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PositionDomain_019d2478-bcaa-7750-95b4-5248684bf050_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PositionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PositionAxis_019d2478-bcaa-7750-95b4-5248684bf050" xlink:to="loc_us-gaap_PositionDomain_019d2478-bcaa-7750-95b4-5248684bf050_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PositionDomain_019d2478-bcaa-73b6-9dfb-a38a8a5b4696" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PositionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PositionAxis_019d2478-bcaa-7750-95b4-5248684bf050" xlink:to="loc_us-gaap_PositionDomain_019d2478-bcaa-73b6-9dfb-a38a8a5b4696" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShortMember_019d2478-bcaa-73da-8a40-eb3e7cbceaac" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShortMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PositionDomain_019d2478-bcaa-73b6-9dfb-a38a8a5b4696" xlink:to="loc_us-gaap_ShortMember_019d2478-bcaa-73da-8a40-eb3e7cbceaac" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongMember_019d2478-bcaa-7722-96bb-648b066e6a46" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PositionDomain_019d2478-bcaa-73b6-9dfb-a38a8a5b4696" xlink:to="loc_us-gaap_LongMember_019d2478-bcaa-7722-96bb-648b066e6a46" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeNotionalAmount_019d2478-bcaa-72ef-bb0e-ade057d4ee59" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeNotionalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_019d2478-bcaa-7926-adb0-3559769909cd" xlink:to="loc_us-gaap_DerivativeNotionalAmount_019d2478-bcaa-72ef-bb0e-ade057d4ee59" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.exlservice.com/role/DerivativesandHedgeAccountingForeignCurrencyForwardContractsDetails" xlink:type="simple" xlink:href="exls-20260331.xsd#DerivativesandHedgeAccountingForeignCurrencyForwardContractsDetails"/>
  <link:definitionLink xlink:role="http://www.exlservice.com/role/DerivativesandHedgeAccountingForeignCurrencyForwardContractsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativesFairValueLineItems_019d2478-bcaa-7f9a-ba95-ded95fcc9fd8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativesFairValueLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable_019d2478-bcaa-7682-af79-8ab721094ec8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativesFairValueLineItems_019d2478-bcaa-7f9a-ba95-ded95fcc9fd8" xlink:to="loc_us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable_019d2478-bcaa-7682-af79-8ab721094ec8" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_019d2478-bcaa-7987-90cf-1c87cbd99eba" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable_019d2478-bcaa-7682-af79-8ab721094ec8" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_019d2478-bcaa-7987-90cf-1c87cbd99eba" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019d2478-bcaa-7987-90cf-1c87cbd99eba_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019d2478-bcaa-7987-90cf-1c87cbd99eba" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019d2478-bcaa-7987-90cf-1c87cbd99eba_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019d2478-bcaa-72f5-ac53-e7f37232ff81" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019d2478-bcaa-7987-90cf-1c87cbd99eba" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019d2478-bcaa-72f5-ac53-e7f37232ff81" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignExchangeContractMember_019d2478-bcaa-7d28-8957-43dc9eaeac70" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ForeignExchangeContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019d2478-bcaa-72f5-ac53-e7f37232ff81" xlink:to="loc_us-gaap_ForeignExchangeContractMember_019d2478-bcaa-7d28-8957-43dc9eaeac70" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationAxis_019d2478-bcaa-789a-9cc9-63a17a05f1bd" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_HedgingDesignationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable_019d2478-bcaa-7682-af79-8ab721094ec8" xlink:to="loc_us-gaap_HedgingDesignationAxis_019d2478-bcaa-789a-9cc9-63a17a05f1bd" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain_019d2478-bcaa-789a-9cc9-63a17a05f1bd_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_HedgingDesignationAxis_019d2478-bcaa-789a-9cc9-63a17a05f1bd" xlink:to="loc_us-gaap_HedgingDesignationDomain_019d2478-bcaa-789a-9cc9-63a17a05f1bd_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain_019d2478-bcaa-7982-9f90-02ea47c200b8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_HedgingDesignationAxis_019d2478-bcaa-789a-9cc9-63a17a05f1bd" xlink:to="loc_us-gaap_HedgingDesignationDomain_019d2478-bcaa-7982-9f90-02ea47c200b8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NondesignatedMember_019d2478-bcaa-7338-ba13-312dcd742e12" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NondesignatedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingDesignationDomain_019d2478-bcaa-7982-9f90-02ea47c200b8" xlink:to="loc_us-gaap_NondesignatedMember_019d2478-bcaa-7338-ba13-312dcd742e12" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PositionAxis_019d2478-bcaa-7b20-9449-aac8a74ec4ed" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PositionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable_019d2478-bcaa-7682-af79-8ab721094ec8" xlink:to="loc_us-gaap_PositionAxis_019d2478-bcaa-7b20-9449-aac8a74ec4ed" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PositionDomain_019d2478-bcaa-7b20-9449-aac8a74ec4ed_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PositionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PositionAxis_019d2478-bcaa-7b20-9449-aac8a74ec4ed" xlink:to="loc_us-gaap_PositionDomain_019d2478-bcaa-7b20-9449-aac8a74ec4ed_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PositionDomain_019d2478-bcaa-71ad-8597-e843d449ad91" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PositionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PositionAxis_019d2478-bcaa-7b20-9449-aac8a74ec4ed" xlink:to="loc_us-gaap_PositionDomain_019d2478-bcaa-71ad-8597-e843d449ad91" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShortMember_019d2478-bcaa-7637-aee5-4340eaed10fd" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShortMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PositionDomain_019d2478-bcaa-71ad-8597-e843d449ad91" xlink:to="loc_us-gaap_ShortMember_019d2478-bcaa-7637-aee5-4340eaed10fd" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongMember_019d2478-bcaa-7450-90ff-e4ba7d7d918a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PositionDomain_019d2478-bcaa-71ad-8597-e843d449ad91" xlink:to="loc_us-gaap_LongMember_019d2478-bcaa-7450-90ff-e4ba7d7d918a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeNotionalAmount_019d2478-bcaa-7d16-afad-aa70155c237c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeNotionalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativesFairValueLineItems_019d2478-bcaa-7f9a-ba95-ded95fcc9fd8" xlink:to="loc_us-gaap_DerivativeNotionalAmount_019d2478-bcaa-7d16-afad-aa70155c237c" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.exlservice.com/role/DerivativesandHedgeAccountingSummaryofFairValueofForeignCurrencyExchangeContractsDetails" xlink:type="simple" xlink:href="exls-20260331.xsd#DerivativesandHedgeAccountingSummaryofFairValueofForeignCurrencyExchangeContractsDetails"/>
  <link:definitionLink xlink:role="http://www.exlservice.com/role/DerivativesandHedgeAccountingSummaryofFairValueofForeignCurrencyExchangeContractsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativesFairValueLineItems_019d2478-bcaa-70e3-8d3e-46b85125eaed" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativesFairValueLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable_019d2478-bcaa-708d-a768-c489aaac31ab" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativesFairValueLineItems_019d2478-bcaa-70e3-8d3e-46b85125eaed" xlink:to="loc_us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable_019d2478-bcaa-708d-a768-c489aaac31ab" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationAxis_019d2478-bcaa-7bac-8d68-b1597945f343" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_HedgingDesignationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable_019d2478-bcaa-708d-a768-c489aaac31ab" xlink:to="loc_us-gaap_HedgingDesignationAxis_019d2478-bcaa-7bac-8d68-b1597945f343" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain_019d2478-bcaa-7bac-8d68-b1597945f343_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_HedgingDesignationAxis_019d2478-bcaa-7bac-8d68-b1597945f343" xlink:to="loc_us-gaap_HedgingDesignationDomain_019d2478-bcaa-7bac-8d68-b1597945f343_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain_019d2478-bcaa-7390-b728-fc579f927484" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_HedgingDesignationAxis_019d2478-bcaa-7bac-8d68-b1597945f343" xlink:to="loc_us-gaap_HedgingDesignationDomain_019d2478-bcaa-7390-b728-fc579f927484" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DesignatedAsHedgingInstrumentMember_019d2478-bcaa-723c-9215-8a910b14139d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DesignatedAsHedgingInstrumentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingDesignationDomain_019d2478-bcaa-7390-b728-fc579f927484" xlink:to="loc_us-gaap_DesignatedAsHedgingInstrumentMember_019d2478-bcaa-723c-9215-8a910b14139d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NondesignatedMember_019d2478-bcaa-7c62-be11-9675cde7eaa6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NondesignatedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingDesignationDomain_019d2478-bcaa-7390-b728-fc579f927484" xlink:to="loc_us-gaap_NondesignatedMember_019d2478-bcaa-7c62-be11-9675cde7eaa6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BalanceSheetLocationAxis_019d2478-bcaa-7157-896b-fea3b24af359" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BalanceSheetLocationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable_019d2478-bcaa-708d-a768-c489aaac31ab" xlink:to="loc_us-gaap_BalanceSheetLocationAxis_019d2478-bcaa-7157-896b-fea3b24af359" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BalanceSheetLocationDomain_019d2478-bcaa-7157-896b-fea3b24af359_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BalanceSheetLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BalanceSheetLocationAxis_019d2478-bcaa-7157-896b-fea3b24af359" xlink:to="loc_us-gaap_BalanceSheetLocationDomain_019d2478-bcaa-7157-896b-fea3b24af359_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BalanceSheetLocationDomain_019d2478-bcaa-79ba-a759-e108bf548c42" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BalanceSheetLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BalanceSheetLocationAxis_019d2478-bcaa-7157-896b-fea3b24af359" xlink:to="loc_us-gaap_BalanceSheetLocationDomain_019d2478-bcaa-79ba-a759-e108bf548c42" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCurrentAssetsMember_019d2478-bcaa-7e23-aaba-e64426179889" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherCurrentAssetsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BalanceSheetLocationDomain_019d2478-bcaa-79ba-a759-e108bf548c42" xlink:to="loc_us-gaap_OtherCurrentAssetsMember_019d2478-bcaa-7e23-aaba-e64426179889" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherAssetsMember_019d2478-bcaa-72ed-8387-9e4a5fbae434" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherAssetsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BalanceSheetLocationDomain_019d2478-bcaa-79ba-a759-e108bf548c42" xlink:to="loc_us-gaap_OtherAssetsMember_019d2478-bcaa-72ed-8387-9e4a5fbae434" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_AccruedExpensesAndOtherCurrentLiabilitiesMember_019d2478-bcaa-76cb-adf7-430e8e777200" xlink:href="exls-20260331.xsd#exls_AccruedExpensesAndOtherCurrentLiabilitiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BalanceSheetLocationDomain_019d2478-bcaa-79ba-a759-e108bf548c42" xlink:to="loc_exls_AccruedExpensesAndOtherCurrentLiabilitiesMember_019d2478-bcaa-76cb-adf7-430e8e777200" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherNoncurrentLiabilitiesMember_019d2478-bcaa-7b53-9332-2124489c0a99" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherNoncurrentLiabilitiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BalanceSheetLocationDomain_019d2478-bcaa-79ba-a759-e108bf548c42" xlink:to="loc_us-gaap_OtherNoncurrentLiabilitiesMember_019d2478-bcaa-7b53-9332-2124489c0a99" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeFairValueOfDerivativeAsset_019d2478-bcaa-79b3-a1dd-bce07b8a01f3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeFairValueOfDerivativeAsset"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativesFairValueLineItems_019d2478-bcaa-70e3-8d3e-46b85125eaed" xlink:to="loc_us-gaap_DerivativeFairValueOfDerivativeAsset_019d2478-bcaa-79b3-a1dd-bce07b8a01f3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeFairValueOfDerivativeLiability_019d2478-bcaa-769a-b202-3d344da6c13c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeFairValueOfDerivativeLiability"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativesFairValueLineItems_019d2478-bcaa-70e3-8d3e-46b85125eaed" xlink:to="loc_us-gaap_DerivativeFairValueOfDerivativeLiability_019d2478-bcaa-769a-b202-3d344da6c13c" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.exlservice.com/role/DerivativesandHedgeAccountingSummaryofEffectofForeignCurrencyExchangeContractsDetails" xlink:type="simple" xlink:href="exls-20260331.xsd#DerivativesandHedgeAccountingSummaryofEffectofForeignCurrencyExchangeContractsDetails"/>
  <link:definitionLink xlink:role="http://www.exlservice.com/role/DerivativesandHedgeAccountingSummaryofEffectofForeignCurrencyExchangeContractsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019d2478-bcaa-7ec2-af82-5e7b49b08749" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeInstrumentsGainLossLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_019d2478-bcaa-7915-82ed-b93f8826f28f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019d2478-bcaa-7ec2-af82-5e7b49b08749" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_019d2478-bcaa-7915-82ed-b93f8826f28f" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019d2478-bcaa-7641-965f-0cc7525e46ad" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_019d2478-bcaa-7915-82ed-b93f8826f28f" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019d2478-bcaa-7641-965f-0cc7525e46ad" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingRelationshipDomain_019d2478-bcaa-7641-965f-0cc7525e46ad_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_HedgingRelationshipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019d2478-bcaa-7641-965f-0cc7525e46ad" xlink:to="loc_us-gaap_HedgingRelationshipDomain_019d2478-bcaa-7641-965f-0cc7525e46ad_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingRelationshipDomain_019d2478-bcaa-7b56-b2c4-25023d04b2e9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_HedgingRelationshipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019d2478-bcaa-7641-965f-0cc7525e46ad" xlink:to="loc_us-gaap_HedgingRelationshipDomain_019d2478-bcaa-7b56-b2c4-25023d04b2e9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashFlowHedgingMember_019d2478-bcaa-7e37-91f6-8914ebf620eb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashFlowHedgingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingRelationshipDomain_019d2478-bcaa-7b56-b2c4-25023d04b2e9" xlink:to="loc_us-gaap_CashFlowHedgingMember_019d2478-bcaa-7e37-91f6-8914ebf620eb" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueHedgingMember_019d2478-bcaa-7324-984e-8948df8c20fe" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueHedgingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingRelationshipDomain_019d2478-bcaa-7b56-b2c4-25023d04b2e9" xlink:to="loc_us-gaap_FairValueHedgingMember_019d2478-bcaa-7324-984e-8948df8c20fe" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis_019d2478-bcaa-762f-ad67-c098d50fc802" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_019d2478-bcaa-7915-82ed-b93f8826f28f" xlink:to="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis_019d2478-bcaa-762f-ad67-c098d50fc802" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain_019d2478-bcaa-762f-ad67-c098d50fc802_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis_019d2478-bcaa-762f-ad67-c098d50fc802" xlink:to="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain_019d2478-bcaa-762f-ad67-c098d50fc802_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain_019d2478-bcaa-7654-8778-bc83e71c66cc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis_019d2478-bcaa-762f-ad67-c098d50fc802" xlink:to="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain_019d2478-bcaa-7654-8778-bc83e71c66cc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember_019d2478-bcaa-7fea-8934-640cb75df482" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain_019d2478-bcaa-7654-8778-bc83e71c66cc" xlink:to="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember_019d2478-bcaa-7fea-8934-640cb75df482" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationAxis_019d2478-bcaa-712d-9a60-b74782d3f82d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_HedgingDesignationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_019d2478-bcaa-7915-82ed-b93f8826f28f" xlink:to="loc_us-gaap_HedgingDesignationAxis_019d2478-bcaa-712d-9a60-b74782d3f82d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain_019d2478-bcaa-712d-9a60-b74782d3f82d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_HedgingDesignationAxis_019d2478-bcaa-712d-9a60-b74782d3f82d" xlink:to="loc_us-gaap_HedgingDesignationDomain_019d2478-bcaa-712d-9a60-b74782d3f82d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain_019d2478-bcaa-79ab-a592-8d3f2a94a0bc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_HedgingDesignationAxis_019d2478-bcaa-712d-9a60-b74782d3f82d" xlink:to="loc_us-gaap_HedgingDesignationDomain_019d2478-bcaa-79ab-a592-8d3f2a94a0bc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DesignatedAsHedgingInstrumentMember_019d2478-bcaa-7eff-a53e-1310d675cf77" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DesignatedAsHedgingInstrumentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingDesignationDomain_019d2478-bcaa-79ab-a592-8d3f2a94a0bc" xlink:to="loc_us-gaap_DesignatedAsHedgingInstrumentMember_019d2478-bcaa-7eff-a53e-1310d675cf77" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NondesignatedMember_019d2478-bcaa-711a-8a29-a34f491d43a5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NondesignatedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingDesignationDomain_019d2478-bcaa-79ab-a592-8d3f2a94a0bc" xlink:to="loc_us-gaap_NondesignatedMember_019d2478-bcaa-711a-8a29-a34f491d43a5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax_019d2478-bcaa-788d-9523-6c06a27d14de" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019d2478-bcaa-7ec2-af82-5e7b49b08749" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax_019d2478-bcaa-788d-9523-6c06a27d14de" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignCurrencyTransactionGainLossBeforeTax_019d2478-bcaa-7afc-bfdb-5a9d32794ea7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ForeignCurrencyTransactionGainLossBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019d2478-bcaa-7ec2-af82-5e7b49b08749" xlink:to="loc_us-gaap_ForeignCurrencyTransactionGainLossBeforeTax_019d2478-bcaa-7afc-bfdb-5a9d32794ea7" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.exlservice.com/role/DerivativesandHedgeAccountingLocationofGainorLossRecognizedDetails" xlink:type="simple" xlink:href="exls-20260331.xsd#DerivativesandHedgeAccountingLocationofGainorLossRecognizedDetails"/>
  <link:definitionLink xlink:role="http://www.exlservice.com/role/DerivativesandHedgeAccountingLocationofGainorLossRecognizedDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019d2478-bcaa-70dd-a2a0-92290bcbe073" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeInstrumentsGainLossLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_019d2478-bcaa-75fa-aa48-0147d5f304c4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019d2478-bcaa-70dd-a2a0-92290bcbe073" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_019d2478-bcaa-75fa-aa48-0147d5f304c4" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis_019d2478-bcaa-7f9b-9e67-e57cb2d67501" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_019d2478-bcaa-75fa-aa48-0147d5f304c4" xlink:to="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis_019d2478-bcaa-7f9b-9e67-e57cb2d67501" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain_019d2478-bcaa-7f9b-9e67-e57cb2d67501_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis_019d2478-bcaa-7f9b-9e67-e57cb2d67501" xlink:to="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain_019d2478-bcaa-7f9b-9e67-e57cb2d67501_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain_019d2478-bcaa-74a9-9fad-7c33cdc42b75" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis_019d2478-bcaa-7f9b-9e67-e57cb2d67501" xlink:to="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain_019d2478-bcaa-74a9-9fad-7c33cdc42b75" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember_019d2478-bcaa-715c-9dca-3bb3dfbb7f65" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain_019d2478-bcaa-74a9-9fad-7c33cdc42b75" xlink:to="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember_019d2478-bcaa-715c-9dca-3bb3dfbb7f65" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationAxis_019d2478-bcaa-78ad-a1ff-faf1274df2ee" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_HedgingDesignationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_019d2478-bcaa-75fa-aa48-0147d5f304c4" xlink:to="loc_us-gaap_HedgingDesignationAxis_019d2478-bcaa-78ad-a1ff-faf1274df2ee" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain_019d2478-bcaa-78ad-a1ff-faf1274df2ee_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_HedgingDesignationAxis_019d2478-bcaa-78ad-a1ff-faf1274df2ee" xlink:to="loc_us-gaap_HedgingDesignationDomain_019d2478-bcaa-78ad-a1ff-faf1274df2ee_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain_019d2478-bcaa-7b60-be64-928a3ebbb596" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_HedgingDesignationAxis_019d2478-bcaa-78ad-a1ff-faf1274df2ee" xlink:to="loc_us-gaap_HedgingDesignationDomain_019d2478-bcaa-7b60-be64-928a3ebbb596" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DesignatedAsHedgingInstrumentMember_019d2478-bcaa-7eb8-8188-070857f2bd45" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DesignatedAsHedgingInstrumentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingDesignationDomain_019d2478-bcaa-7b60-be64-928a3ebbb596" xlink:to="loc_us-gaap_DesignatedAsHedgingInstrumentMember_019d2478-bcaa-7eb8-8188-070857f2bd45" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NondesignatedMember_019d2478-bcaa-7073-867b-aab76c8397e3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NondesignatedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingDesignationDomain_019d2478-bcaa-7b60-be64-928a3ebbb596" xlink:to="loc_us-gaap_NondesignatedMember_019d2478-bcaa-7073-867b-aab76c8397e3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019d2478-bcaa-704c-a212-216b42e8166c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_019d2478-bcaa-75fa-aa48-0147d5f304c4" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019d2478-bcaa-704c-a212-216b42e8166c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingRelationshipDomain_019d2478-bcaa-704c-a212-216b42e8166c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_HedgingRelationshipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019d2478-bcaa-704c-a212-216b42e8166c" xlink:to="loc_us-gaap_HedgingRelationshipDomain_019d2478-bcaa-704c-a212-216b42e8166c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingRelationshipDomain_019d2478-bcaa-7646-9d00-0503e3b19435" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_HedgingRelationshipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019d2478-bcaa-704c-a212-216b42e8166c" xlink:to="loc_us-gaap_HedgingRelationshipDomain_019d2478-bcaa-7646-9d00-0503e3b19435" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashFlowHedgingMember_019d2478-bcaa-7d07-8566-56443f424c7e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashFlowHedgingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingRelationshipDomain_019d2478-bcaa-7646-9d00-0503e3b19435" xlink:to="loc_us-gaap_CashFlowHedgingMember_019d2478-bcaa-7d07-8566-56443f424c7e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueHedgingMember_019d2478-bcaa-792e-bdd3-a5825c080ce0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueHedgingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingRelationshipDomain_019d2478-bcaa-7646-9d00-0503e3b19435" xlink:to="loc_us-gaap_FairValueHedgingMember_019d2478-bcaa-792e-bdd3-a5825c080ce0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Revenues_019d2478-bcaa-7c56-aec3-0d3c8c8429f4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Revenues"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019d2478-bcaa-70dd-a2a0-92290bcbe073" xlink:to="loc_us-gaap_Revenues_019d2478-bcaa-7c56-aec3-0d3c8c8429f4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortization_019d2478-bcaa-7bc1-ba18-3bf7c3e64dfa" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019d2478-bcaa-70dd-a2a0-92290bcbe073" xlink:to="loc_us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortization_019d2478-bcaa-7bc1-ba18-3bf7c3e64dfa" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GeneralAndAdministrativeExpense_019d2478-bcaa-7530-acc4-1dfcd49c08e2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GeneralAndAdministrativeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019d2478-bcaa-70dd-a2a0-92290bcbe073" xlink:to="loc_us-gaap_GeneralAndAdministrativeExpense_019d2478-bcaa-7530-acc4-1dfcd49c08e2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SellingAndMarketingExpense_019d2478-bcaa-7875-b53c-f11955b31bab" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SellingAndMarketingExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019d2478-bcaa-70dd-a2a0-92290bcbe073" xlink:to="loc_us-gaap_SellingAndMarketingExpense_019d2478-bcaa-7875-b53c-f11955b31bab" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepreciationAndAmortization_019d2478-bcaa-7c5c-b614-cffbbdd3f97c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DepreciationAndAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019d2478-bcaa-70dd-a2a0-92290bcbe073" xlink:to="loc_us-gaap_DepreciationAndAmortization_019d2478-bcaa-7c5c-b614-cffbbdd3f97c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_019d2478-bcaa-76f4-ad14-8c77876e1a1d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019d2478-bcaa-70dd-a2a0-92290bcbe073" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_019d2478-bcaa-76f4-ad14-8c77876e1a1d" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_019d2478-bcaa-7bc5-87de-a33c18979450" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxExpenseBenefit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019d2478-bcaa-70dd-a2a0-92290bcbe073" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_019d2478-bcaa-7bc5-87de-a33c18979450" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_019d2478-bcaa-7198-9676-77fd6a09888f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019d2478-bcaa-70dd-a2a0-92290bcbe073" xlink:to="loc_us-gaap_NetIncomeLoss_019d2478-bcaa-7198-9676-77fd6a09888f" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignCurrencyTransactionGainLossBeforeTax_019d2478-bcaa-7b65-9566-36a6d8326d97" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ForeignCurrencyTransactionGainLossBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019d2478-bcaa-70dd-a2a0-92290bcbe073" xlink:to="loc_us-gaap_ForeignCurrencyTransactionGainLossBeforeTax_019d2478-bcaa-7b65-9566-36a6d8326d97" xlink:type="arc" order="8"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.exlservice.com/role/BorrowingsCompanysDebtPositionDetails" xlink:type="simple" xlink:href="exls-20260331.xsd#BorrowingsCompanysDebtPositionDetails"/>
  <link:definitionLink xlink:role="http://www.exlservice.com/role/BorrowingsCompanysDebtPositionDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_019d2478-bcaa-7f08-9244-04598899ccd8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTable_019d2478-bcaa-7c78-9f6e-17d9b0b7a8d8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019d2478-bcaa-7f08-9244-04598899ccd8" xlink:to="loc_us-gaap_DebtInstrumentTable_019d2478-bcaa-7c78-9f6e-17d9b0b7a8d8" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityAxis_019d2478-bcaa-7de6-88dd-4fee2b124666" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_019d2478-bcaa-7c78-9f6e-17d9b0b7a8d8" xlink:to="loc_us-gaap_CreditFacilityAxis_019d2478-bcaa-7de6-88dd-4fee2b124666" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_019d2478-bcaa-7de6-88dd-4fee2b124666_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditFacilityAxis_019d2478-bcaa-7de6-88dd-4fee2b124666" xlink:to="loc_us-gaap_CreditFacilityDomain_019d2478-bcaa-7de6-88dd-4fee2b124666_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_019d2478-bcaa-79c7-89e0-cd9744ab5707" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditFacilityAxis_019d2478-bcaa-7de6-88dd-4fee2b124666" xlink:to="loc_us-gaap_CreditFacilityDomain_019d2478-bcaa-79c7-89e0-cd9744ab5707" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevolvingCreditFacilityMember_019d2478-bcaa-7506-bf2b-3d183e221860" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevolvingCreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_019d2478-bcaa-79c7-89e0-cd9744ab5707" xlink:to="loc_us-gaap_RevolvingCreditFacilityMember_019d2478-bcaa-7506-bf2b-3d183e221860" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuredDebtMember_019d2478-bcaa-7119-bc8c-89ea3efd1909" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SecuredDebtMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_019d2478-bcaa-79c7-89e0-cd9744ab5707" xlink:to="loc_us-gaap_SecuredDebtMember_019d2478-bcaa-7119-bc8c-89ea3efd1909" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_019d2478-bcaa-7dbb-bda6-8841101b455d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_019d2478-bcaa-7c78-9f6e-17d9b0b7a8d8" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_019d2478-bcaa-7dbb-bda6-8841101b455d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019d2478-bcaa-7dbb-bda6-8841101b455d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_019d2478-bcaa-7dbb-bda6-8841101b455d" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019d2478-bcaa-7dbb-bda6-8841101b455d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019d2478-bcaa-7ca6-868d-82498a270ab1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_019d2478-bcaa-7dbb-bda6-8841101b455d" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019d2478-bcaa-7ca6-868d-82498a270ab1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditMember_019d2478-bcaa-70d0-8e66-34a9b7d92653" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LineOfCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_019d2478-bcaa-7ca6-868d-82498a270ab1" xlink:to="loc_us-gaap_LineOfCreditMember_019d2478-bcaa-70d0-8e66-34a9b7d92653" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_LongTermDebtCurrentMaturitiesGross_019d2478-bcaa-7923-9f0d-aba73cbbef22" xlink:href="exls-20260331.xsd#exls_LongTermDebtCurrentMaturitiesGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019d2478-bcaa-7f08-9244-04598899ccd8" xlink:to="loc_exls_LongTermDebtCurrentMaturitiesGross_019d2478-bcaa-7923-9f0d-aba73cbbef22" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredFinanceCostsCurrentNet_019d2478-bcaa-70ca-bbb7-bd34abba8133" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DeferredFinanceCostsCurrentNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019d2478-bcaa-7f08-9244-04598899ccd8" xlink:to="loc_us-gaap_DeferredFinanceCostsCurrentNet_019d2478-bcaa-70ca-bbb7-bd34abba8133" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtCurrent_019d2478-bcaa-7e36-aece-55e0ba297f02" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermDebtCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019d2478-bcaa-7f08-9244-04598899ccd8" xlink:to="loc_us-gaap_LongTermDebtCurrent_019d2478-bcaa-7e36-aece-55e0ba297f02" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermLineOfCredit_019d2478-bcaa-756a-82e0-219efe0847a1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermLineOfCredit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019d2478-bcaa-7f08-9244-04598899ccd8" xlink:to="loc_us-gaap_LongTermLineOfCredit_019d2478-bcaa-756a-82e0-219efe0847a1" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredFinanceCostsNoncurrentNet_019d2478-bcaa-722d-b675-48a7cf07ffc4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DeferredFinanceCostsNoncurrentNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019d2478-bcaa-7f08-9244-04598899ccd8" xlink:to="loc_us-gaap_DeferredFinanceCostsNoncurrentNet_019d2478-bcaa-722d-b675-48a7cf07ffc4" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtNoncurrent_019d2478-bcaa-74ba-b6b8-93a259d5f10f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermDebtNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019d2478-bcaa-7f08-9244-04598899ccd8" xlink:to="loc_us-gaap_LongTermDebtNoncurrent_019d2478-bcaa-74ba-b6b8-93a259d5f10f" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebt_019d2478-bcaa-766d-806f-66bb390f722b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019d2478-bcaa-7f08-9244-04598899ccd8" xlink:to="loc_us-gaap_LongTermDebt_019d2478-bcaa-766d-806f-66bb390f722b" xlink:type="arc" order="6"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.exlservice.com/role/BorrowingsAdditionalInformationDetails" xlink:type="simple" xlink:href="exls-20260331.xsd#BorrowingsAdditionalInformationDetails"/>
  <link:definitionLink xlink:role="http://www.exlservice.com/role/BorrowingsAdditionalInformationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityLineItems_019d2478-bcaa-7424-80f6-158e4740f617" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LineOfCreditFacilityLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityTable_019d2478-bcaa-711a-ac8d-77fe7ba2a358" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LineOfCreditFacilityTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_019d2478-bcaa-7424-80f6-158e4740f617" xlink:to="loc_us-gaap_LineOfCreditFacilityTable_019d2478-bcaa-711a-ac8d-77fe7ba2a358" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityAxis_019d2478-bcaa-7079-b4d4-3342f79a3301" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LineOfCreditFacilityTable_019d2478-bcaa-711a-ac8d-77fe7ba2a358" xlink:to="loc_us-gaap_CreditFacilityAxis_019d2478-bcaa-7079-b4d4-3342f79a3301" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_019d2478-bcaa-7079-b4d4-3342f79a3301_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditFacilityAxis_019d2478-bcaa-7079-b4d4-3342f79a3301" xlink:to="loc_us-gaap_CreditFacilityDomain_019d2478-bcaa-7079-b4d4-3342f79a3301_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_019d2478-bcaa-7a0c-a0b6-e010b86f72d4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditFacilityAxis_019d2478-bcaa-7079-b4d4-3342f79a3301" xlink:to="loc_us-gaap_CreditFacilityDomain_019d2478-bcaa-7a0c-a0b6-e010b86f72d4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevolvingCreditFacilityMember_019d2478-bcaa-7c5d-acab-a1135f66eaed" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevolvingCreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_019d2478-bcaa-7a0c-a0b6-e010b86f72d4" xlink:to="loc_us-gaap_RevolvingCreditFacilityMember_019d2478-bcaa-7c5d-acab-a1135f66eaed" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuredDebtMember_019d433c-01f4-7bf4-a8da-e47aedf77d70" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SecuredDebtMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_019d2478-bcaa-7a0c-a0b6-e010b86f72d4" xlink:to="loc_us-gaap_SecuredDebtMember_019d433c-01f4-7bf4-a8da-e47aedf77d70" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_019d2478-bcaa-78e7-b343-7996713dad4c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LineOfCreditFacilityTable_019d2478-bcaa-711a-ac8d-77fe7ba2a358" xlink:to="loc_us-gaap_DebtInstrumentAxis_019d2478-bcaa-78e7-b343-7996713dad4c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019d2478-bcaa-78e7-b343-7996713dad4c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_019d2478-bcaa-78e7-b343-7996713dad4c" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019d2478-bcaa-78e7-b343-7996713dad4c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019d2478-bcaa-7f7e-8486-7c6c788e70de" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_019d2478-bcaa-78e7-b343-7996713dad4c" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019d2478-bcaa-7f7e-8486-7c6c788e70de" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_CreditAgreementMember_019d2478-bcaa-76ff-bdbc-471dfe95c131" xlink:href="exls-20260331.xsd#exls_CreditAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019d2478-bcaa-7f7e-8486-7c6c788e70de" xlink:to="loc_exls_CreditAgreementMember_019d2478-bcaa-76ff-bdbc-471dfe95c131" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_019d2478-bcaa-74f9-929f-b826656ae22d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LineOfCreditFacilityTable_019d2478-bcaa-711a-ac8d-77fe7ba2a358" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_019d2478-bcaa-74f9-929f-b826656ae22d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019d2478-bcaa-74f9-929f-b826656ae22d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_019d2478-bcaa-74f9-929f-b826656ae22d" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019d2478-bcaa-74f9-929f-b826656ae22d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019d2478-bcaa-7131-a438-c97fcdcb67c6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_019d2478-bcaa-74f9-929f-b826656ae22d" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019d2478-bcaa-7131-a438-c97fcdcb67c6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditMember_019d2478-bcaa-7503-ac08-19420a139788" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LineOfCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_019d2478-bcaa-7131-a438-c97fcdcb67c6" xlink:to="loc_us-gaap_LineOfCreditMember_019d2478-bcaa-7503-ac08-19420a139788" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnamortizedDebtIssuanceExpense_019d2478-bcaa-7374-a9a1-ad27e0348163" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_UnamortizedDebtIssuanceExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_019d2478-bcaa-7424-80f6-158e4740f617" xlink:to="loc_us-gaap_UnamortizedDebtIssuanceExpense_019d2478-bcaa-7374-a9a1-ad27e0348163" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_019d2478-bcaa-7d3f-9522-8eb96b220418" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_019d2478-bcaa-7424-80f6-158e4740f617" xlink:to="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_019d2478-bcaa-7d3f-9522-8eb96b220418" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromLongTermLinesOfCredit_019d2478-bcaa-718d-861a-25f078f908ab" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProceedsFromLongTermLinesOfCredit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_019d2478-bcaa-7424-80f6-158e4740f617" xlink:to="loc_us-gaap_ProceedsFromLongTermLinesOfCredit_019d2478-bcaa-718d-861a-25f078f908ab" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_019d2478-bcaa-7b72-86a8-e45948a250bb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_019d2478-bcaa-7424-80f6-158e4740f617" xlink:to="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_019d2478-bcaa-7b72-86a8-e45948a250bb" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LettersOfCreditOutstandingAmount_019d2478-bcaa-7af5-8ee7-1d30e2c0ddcf" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LettersOfCreditOutstandingAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_019d2478-bcaa-7424-80f6-158e4740f617" xlink:to="loc_us-gaap_LettersOfCreditOutstandingAmount_019d2478-bcaa-7af5-8ee7-1d30e2c0ddcf" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.exlservice.com/role/BorrowingsCreditFacilitiesCarriedanEffectiveInterestRateDetails" xlink:type="simple" xlink:href="exls-20260331.xsd#BorrowingsCreditFacilitiesCarriedanEffectiveInterestRateDetails"/>
  <link:definitionLink xlink:role="http://www.exlservice.com/role/BorrowingsCreditFacilitiesCarriedanEffectiveInterestRateDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_019d2478-bcaa-754a-b48c-dfbed2c8fd59" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTable_019d2478-bcaa-7240-baa0-e188596538e6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019d2478-bcaa-754a-b48c-dfbed2c8fd59" xlink:to="loc_us-gaap_DebtInstrumentTable_019d2478-bcaa-7240-baa0-e188596538e6" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityAxis_019d2478-bcaa-7609-b852-ba46e973fc6e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_019d2478-bcaa-7240-baa0-e188596538e6" xlink:to="loc_us-gaap_CreditFacilityAxis_019d2478-bcaa-7609-b852-ba46e973fc6e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_019d2478-bcaa-7609-b852-ba46e973fc6e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditFacilityAxis_019d2478-bcaa-7609-b852-ba46e973fc6e" xlink:to="loc_us-gaap_CreditFacilityDomain_019d2478-bcaa-7609-b852-ba46e973fc6e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_019d2478-bcaa-7e36-9117-f881f80f527b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditFacilityAxis_019d2478-bcaa-7609-b852-ba46e973fc6e" xlink:to="loc_us-gaap_CreditFacilityDomain_019d2478-bcaa-7e36-9117-f881f80f527b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevolvingCreditFacilityMember_019d2478-bcaa-7553-84d4-b0e9090254a5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevolvingCreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_019d2478-bcaa-7e36-9117-f881f80f527b" xlink:to="loc_us-gaap_RevolvingCreditFacilityMember_019d2478-bcaa-7553-84d4-b0e9090254a5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuredDebtMember_019d2478-bcaa-7c5d-af53-f9f8835ce527" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SecuredDebtMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_019d2478-bcaa-7e36-9117-f881f80f527b" xlink:to="loc_us-gaap_SecuredDebtMember_019d2478-bcaa-7c5d-af53-f9f8835ce527" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_019d2478-bcaa-72a6-808c-aa0c2fe73586" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_019d2478-bcaa-7240-baa0-e188596538e6" xlink:to="loc_us-gaap_DebtInstrumentAxis_019d2478-bcaa-72a6-808c-aa0c2fe73586" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019d2478-bcaa-72a6-808c-aa0c2fe73586_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_019d2478-bcaa-72a6-808c-aa0c2fe73586" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019d2478-bcaa-72a6-808c-aa0c2fe73586_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019d2478-bcaa-7624-8d0e-0bfc9f50a676" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_019d2478-bcaa-72a6-808c-aa0c2fe73586" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019d2478-bcaa-7624-8d0e-0bfc9f50a676" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_CreditAgreementMember_019d2478-bcaa-7df7-bc1d-f7b9871dcc78" xlink:href="exls-20260331.xsd#exls_CreditAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019d2478-bcaa-7624-8d0e-0bfc9f50a676" xlink:to="loc_exls_CreditAgreementMember_019d2478-bcaa-7df7-bc1d-f7b9871dcc78" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_019d2478-bcaa-71f5-819d-cbabd112dc66" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_019d2478-bcaa-7240-baa0-e188596538e6" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_019d2478-bcaa-71f5-819d-cbabd112dc66" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019d2478-bcaa-71f5-819d-cbabd112dc66_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_019d2478-bcaa-71f5-819d-cbabd112dc66" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019d2478-bcaa-71f5-819d-cbabd112dc66_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019d2478-bcaa-7def-b4c6-ef79f97a234d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_019d2478-bcaa-71f5-819d-cbabd112dc66" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019d2478-bcaa-7def-b4c6-ef79f97a234d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditMember_019d2478-bcaa-7057-b6ce-d4594b041a12" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LineOfCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_019d2478-bcaa-7def-b4c6-ef79f97a234d" xlink:to="loc_us-gaap_LineOfCreditMember_019d2478-bcaa-7057-b6ce-d4594b041a12" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityInterestRateDuringPeriod_019d2478-bcaa-7bed-8fc6-b742be934a64" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LineOfCreditFacilityInterestRateDuringPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019d2478-bcaa-754a-b48c-dfbed2c8fd59" xlink:to="loc_us-gaap_LineOfCreditFacilityInterestRateDuringPeriod_019d2478-bcaa-7bed-8fc6-b742be934a64" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.exlservice.com/role/BorrowingsMaturitiesofBorrowingsDetails" xlink:type="simple" xlink:href="exls-20260331.xsd#BorrowingsMaturitiesofBorrowingsDetails"/>
  <link:definitionLink xlink:role="http://www.exlservice.com/role/BorrowingsMaturitiesofBorrowingsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityLineItems_019d2478-bcaa-7a3f-bdae-eb7eadba0e29" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LineOfCreditFacilityLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTable_019d2478-bcaa-7827-8227-ec2bd7112548" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_019d2478-bcaa-7a3f-bdae-eb7eadba0e29" xlink:to="loc_us-gaap_DebtInstrumentTable_019d2478-bcaa-7827-8227-ec2bd7112548" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityAxis_019d2478-bcaa-72ff-9b88-e33f3941398d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_019d2478-bcaa-7827-8227-ec2bd7112548" xlink:to="loc_us-gaap_CreditFacilityAxis_019d2478-bcaa-72ff-9b88-e33f3941398d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_019d2478-bcaa-72ff-9b88-e33f3941398d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditFacilityAxis_019d2478-bcaa-72ff-9b88-e33f3941398d" xlink:to="loc_us-gaap_CreditFacilityDomain_019d2478-bcaa-72ff-9b88-e33f3941398d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_019d2478-bcaa-715a-8026-e7546ff15287" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditFacilityAxis_019d2478-bcaa-72ff-9b88-e33f3941398d" xlink:to="loc_us-gaap_CreditFacilityDomain_019d2478-bcaa-715a-8026-e7546ff15287" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevolvingCreditFacilityMember_019d2478-bcaa-777d-aafb-a9eaa7a9a017" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevolvingCreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_019d2478-bcaa-715a-8026-e7546ff15287" xlink:to="loc_us-gaap_RevolvingCreditFacilityMember_019d2478-bcaa-777d-aafb-a9eaa7a9a017" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuredDebtMember_019d2478-bcaa-73fd-9be7-34417cd92ad0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SecuredDebtMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_019d2478-bcaa-715a-8026-e7546ff15287" xlink:to="loc_us-gaap_SecuredDebtMember_019d2478-bcaa-73fd-9be7-34417cd92ad0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_019d2478-bcaa-75ba-8b99-83b27a9f391f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_019d2478-bcaa-7827-8227-ec2bd7112548" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_019d2478-bcaa-75ba-8b99-83b27a9f391f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019d2478-bcaa-75ba-8b99-83b27a9f391f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_019d2478-bcaa-75ba-8b99-83b27a9f391f" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019d2478-bcaa-75ba-8b99-83b27a9f391f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019d2478-bcaa-7eac-a6ac-7534940bb052" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_019d2478-bcaa-75ba-8b99-83b27a9f391f" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019d2478-bcaa-7eac-a6ac-7534940bb052" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditMember_019d2478-bcaa-7b2f-ac4a-645b5bbb164d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LineOfCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_019d2478-bcaa-7eac-a6ac-7534940bb052" xlink:to="loc_us-gaap_LineOfCreditMember_019d2478-bcaa-7b2f-ac4a-645b5bbb164d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalRemainderOfFiscalYear_019d2478-bcaa-7c5e-bdab-b683b71ab12a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalRemainderOfFiscalYear"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_019d2478-bcaa-7a3f-bdae-eb7eadba0e29" xlink:to="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalRemainderOfFiscalYear_019d2478-bcaa-7c5e-bdab-b683b71ab12a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths_019d2478-bcaa-7a9b-8480-e3b315d5e375" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_019d2478-bcaa-7a3f-bdae-eb7eadba0e29" xlink:to="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths_019d2478-bcaa-7a9b-8480-e3b315d5e375" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentCarryingAmount_019d2478-bcaa-7866-962a-a8f728bec281" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentCarryingAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_019d2478-bcaa-7a3f-bdae-eb7eadba0e29" xlink:to="loc_us-gaap_DebtInstrumentCarryingAmount_019d2478-bcaa-7866-962a-a8f728bec281" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.exlservice.com/role/CapitalStructureAdditionalInformationDetails" xlink:type="simple" xlink:href="exls-20260331.xsd#CapitalStructureAdditionalInformationDetails"/>
  <link:definitionLink xlink:role="http://www.exlservice.com/role/CapitalStructureAdditionalInformationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityClassOfTreasuryStockLineItems_019d434e-41d7-76a8-bf49-8f7e6205d6cf" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityClassOfTreasuryStockLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfTreasuryStockTable_019d2478-bcaa-75e5-86c0-0c7d4ee6eba1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfTreasuryStockTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_019d434e-41d7-76a8-bf49-8f7e6205d6cf" xlink:to="loc_us-gaap_ClassOfTreasuryStockTable_019d2478-bcaa-75e5-86c0-0c7d4ee6eba1" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramAxis_019d434e-6605-7042-bdaa-be58259a1d65" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ShareRepurchaseProgramAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ClassOfTreasuryStockTable_019d2478-bcaa-75e5-86c0-0c7d4ee6eba1" xlink:to="loc_srt_ShareRepurchaseProgramAxis_019d434e-6605-7042-bdaa-be58259a1d65" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramDomain_019d434e-6605-7042-bdaa-be58259a1d65_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ShareRepurchaseProgramDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ShareRepurchaseProgramAxis_019d434e-6605-7042-bdaa-be58259a1d65" xlink:to="loc_srt_ShareRepurchaseProgramDomain_019d434e-6605-7042-bdaa-be58259a1d65_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramDomain_019d434e-6605-79e0-bf06-ac4b591e3732" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ShareRepurchaseProgramDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ShareRepurchaseProgramAxis_019d434e-6605-7042-bdaa-be58259a1d65" xlink:to="loc_srt_ShareRepurchaseProgramDomain_019d434e-6605-79e0-bf06-ac4b591e3732" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_A2024RepurchaseProgramMember_019d434e-6605-7d39-b7b4-b45f407c63b1" xlink:href="exls-20260331.xsd#exls_A2024RepurchaseProgramMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ShareRepurchaseProgramDomain_019d434e-6605-79e0-bf06-ac4b591e3732" xlink:to="loc_exls_A2024RepurchaseProgramMember_019d434e-6605-7d39-b7b4-b45f407c63b1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_A2026RepurchaseProgramMember_019d434e-6605-70bd-a1a5-1688e41dee9c" xlink:href="exls-20260331.xsd#exls_A2026RepurchaseProgramMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ShareRepurchaseProgramDomain_019d434e-6605-79e0-bf06-ac4b591e3732" xlink:to="loc_exls_A2026RepurchaseProgramMember_019d434e-6605-70bd-a1a5-1688e41dee9c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_A2026AcceleratedShareRepurchaseAgreementASRAgreementMember_019d434e-6605-78dc-a93a-6e25426dae4e" xlink:href="exls-20260331.xsd#exls_A2026AcceleratedShareRepurchaseAgreementASRAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ShareRepurchaseProgramDomain_019d434e-6605-79e0-bf06-ac4b591e3732" xlink:to="loc_exls_A2026AcceleratedShareRepurchaseAgreementASRAgreementMember_019d434e-6605-78dc-a93a-6e25426dae4e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_NumberOfClassesOfCommonStockOutstanding_019d434e-41d7-770e-a4c2-17798bf2bfea" xlink:href="exls-20260331.xsd#exls_NumberOfClassesOfCommonStockOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_019d434e-41d7-76a8-bf49-8f7e6205d6cf" xlink:to="loc_exls_NumberOfClassesOfCommonStockOutstanding_019d434e-41d7-770e-a4c2-17798bf2bfea" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StockRepurchaseProgramAuthorizedAmount1_019d434e-6605-72d9-a1df-7027af6741c9" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_StockRepurchaseProgramAuthorizedAmount1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_019d434e-41d7-76a8-bf49-8f7e6205d6cf" xlink:to="loc_srt_StockRepurchaseProgramAuthorizedAmount1_019d434e-6605-72d9-a1df-7027af6741c9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsForRepurchaseOfCommonStock_019d434e-6605-7363-aa20-07a4d6714d04" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsForRepurchaseOfCommonStock"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_019d434e-41d7-76a8-bf49-8f7e6205d6cf" xlink:to="loc_us-gaap_PaymentsForRepurchaseOfCommonStock_019d434e-6605-7363-aa20-07a4d6714d04" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockSharesAcquired_019d434e-6605-7ff9-8fcd-9aa7c62bcfa6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TreasuryStockSharesAcquired"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_019d434e-41d7-76a8-bf49-8f7e6205d6cf" xlink:to="loc_us-gaap_TreasuryStockSharesAcquired_019d434e-6605-7ff9-8fcd-9aa7c62bcfa6" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AcceleratedShareRepurchasesInitialPricePaidPerShare_019d434e-6605-7fa4-85c8-2ece47b1b42f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AcceleratedShareRepurchasesInitialPricePaidPerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_019d434e-41d7-76a8-bf49-8f7e6205d6cf" xlink:to="loc_us-gaap_AcceleratedShareRepurchasesInitialPricePaidPerShare_019d434e-6605-7fa4-85c8-2ece47b1b42f" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_PercentageOfPrepaymentStockRepurchaseProgramPrepaymentSharesDelivered_019d434e-6605-7e0f-ada7-c1f0019f573c" xlink:href="exls-20260331.xsd#exls_PercentageOfPrepaymentStockRepurchaseProgramPrepaymentSharesDelivered"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_019d434e-41d7-76a8-bf49-8f7e6205d6cf" xlink:to="loc_exls_PercentageOfPrepaymentStockRepurchaseProgramPrepaymentSharesDelivered_019d434e-6605-7e0f-ada7-c1f0019f573c" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_ShareRepurchaseEquityInstrumentsFairValue_019d434e-6605-7333-9631-bc6725e2d06d" xlink:href="exls-20260331.xsd#exls_ShareRepurchaseEquityInstrumentsFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_019d434e-41d7-76a8-bf49-8f7e6205d6cf" xlink:to="loc_exls_ShareRepurchaseEquityInstrumentsFairValue_019d434e-6605-7333-9631-bc6725e2d06d" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ExciseAndSalesTaxes_019d4396-f96b-7c63-b2fe-788e26140282" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ExciseAndSalesTaxes"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_019d434e-41d7-76a8-bf49-8f7e6205d6cf" xlink:to="loc_us-gaap_ExciseAndSalesTaxes_019d4396-f96b-7c63-b2fe-788e26140282" xlink:type="arc" order="7"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.exlservice.com/role/StockBasedCompensationCostsRelatedtoCompanysStockBasedCompensationPlanDetails" xlink:type="simple" xlink:href="exls-20260331.xsd#StockBasedCompensationCostsRelatedtoCompanysStockBasedCompensationPlanDetails"/>
  <link:definitionLink xlink:role="http://www.exlservice.com/role/StockBasedCompensationCostsRelatedtoCompanysStockBasedCompensationPlanDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_019d2478-bcaa-7bf9-a658-f025163456d0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_019d2478-bcaa-7e54-834f-0820912e2acc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_019d2478-bcaa-7bf9-a658-f025163456d0" xlink:to="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_019d2478-bcaa-7e54-834f-0820912e2acc" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationAxis_019d2478-bcaa-7a0a-8ffa-ce2f2c52a357" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeStatementLocationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_019d2478-bcaa-7e54-834f-0820912e2acc" xlink:to="loc_us-gaap_IncomeStatementLocationAxis_019d2478-bcaa-7a0a-8ffa-ce2f2c52a357" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_019d2478-bcaa-7a0a-8ffa-ce2f2c52a357_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeStatementLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_019d2478-bcaa-7a0a-8ffa-ce2f2c52a357" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_019d2478-bcaa-7a0a-8ffa-ce2f2c52a357_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_019d2478-bcaa-76c2-a30b-3c90b28efef0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeStatementLocationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_019d2478-bcaa-7a0a-8ffa-ce2f2c52a357" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_019d2478-bcaa-76c2-a30b-3c90b28efef0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostOfSalesMember_019d2478-bcaa-7bb7-a5f4-8d35eabc5dff" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CostOfSalesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_019d2478-bcaa-76c2-a30b-3c90b28efef0" xlink:to="loc_us-gaap_CostOfSalesMember_019d2478-bcaa-7bb7-a5f4-8d35eabc5dff" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GeneralAndAdministrativeExpenseMember_019d2478-bcaa-7ad0-9482-4f64b54fb9f4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GeneralAndAdministrativeExpenseMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_019d2478-bcaa-76c2-a30b-3c90b28efef0" xlink:to="loc_us-gaap_GeneralAndAdministrativeExpenseMember_019d2478-bcaa-7ad0-9482-4f64b54fb9f4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SellingAndMarketingExpenseMember_019d2478-bcaa-7448-865c-4aba4b62264b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SellingAndMarketingExpenseMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_019d2478-bcaa-76c2-a30b-3c90b28efef0" xlink:to="loc_us-gaap_SellingAndMarketingExpenseMember_019d2478-bcaa-7448-865c-4aba4b62264b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllocatedShareBasedCompensationExpense_019d2478-bcaa-74fc-8db7-0575b141b4f1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AllocatedShareBasedCompensationExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_019d2478-bcaa-7bf9-a658-f025163456d0" xlink:to="loc_us-gaap_AllocatedShareBasedCompensationExpense_019d2478-bcaa-74fc-8db7-0575b141b4f1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense_019d2478-bcaa-74c7-beb7-43362ffb3d53" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_019d2478-bcaa-7bf9-a658-f025163456d0" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense_019d2478-bcaa-74c7-beb7-43362ffb3d53" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_ShareBasedPaymentArrangementExpenseTaxBenefitDiscreteBenefits_019d2478-bcaa-73d1-99c2-49ef60a9ea49" xlink:href="exls-20260331.xsd#exls_ShareBasedPaymentArrangementExpenseTaxBenefitDiscreteBenefits"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_019d2478-bcaa-7bf9-a658-f025163456d0" xlink:to="loc_exls_ShareBasedPaymentArrangementExpenseTaxBenefitDiscreteBenefits_019d2478-bcaa-73d1-99c2-49ef60a9ea49" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.exlservice.com/role/StockBasedCompensationAdditionalInformationDetails" xlink:type="simple" xlink:href="exls-20260331.xsd#StockBasedCompensationAdditionalInformationDetails"/>
  <link:definitionLink xlink:role="http://www.exlservice.com/role/StockBasedCompensationAdditionalInformationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d2478-bcaa-70f7-9dd3-c952726e1f90" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019d2478-bcaa-7af6-a77d-5e9836e45441" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d2478-bcaa-70f7-9dd3-c952726e1f90" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019d2478-bcaa-7af6-a77d-5e9836e45441" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameAxis_019d2478-bcaa-744a-ae46-35c6a202466c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019d2478-bcaa-7af6-a77d-5e9836e45441" xlink:to="loc_us-gaap_PlanNameAxis_019d2478-bcaa-744a-ae46-35c6a202466c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameDomain_019d2478-bcaa-744a-ae46-35c6a202466c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PlanNameAxis_019d2478-bcaa-744a-ae46-35c6a202466c" xlink:to="loc_us-gaap_PlanNameDomain_019d2478-bcaa-744a-ae46-35c6a202466c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameDomain_019d2478-bcaa-7785-aba6-41bfc78bd506" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PlanNameAxis_019d2478-bcaa-744a-ae46-35c6a202466c" xlink:to="loc_us-gaap_PlanNameDomain_019d2478-bcaa-7785-aba6-41bfc78bd506" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_A2025StockOptionsPlanMember_019d4375-1f49-7fc2-8c0e-55baa7772575" xlink:href="exls-20260331.xsd#exls_A2025StockOptionsPlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PlanNameDomain_019d2478-bcaa-7785-aba6-41bfc78bd506" xlink:to="loc_exls_A2025StockOptionsPlanMember_019d4375-1f49-7fc2-8c0e-55baa7772575" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_019d2478-bcaa-7bf8-a378-e8fa6f3784ed" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d2478-bcaa-70f7-9dd3-c952726e1f90" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_019d2478-bcaa-7bf8-a378-e8fa6f3784ed" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.exlservice.com/role/StockBasedCompensationSummaryofStockOptionsDetails" xlink:type="simple" xlink:href="exls-20260331.xsd#StockBasedCompensationSummaryofStockOptionsDetails"/>
  <link:definitionLink xlink:role="http://www.exlservice.com/role/StockBasedCompensationSummaryofStockOptionsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d2478-bcaa-76e7-be96-619c390c917d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019d2478-bcaa-79c5-b17b-052261687970" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d2478-bcaa-76e7-be96-619c390c917d" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019d2478-bcaa-79c5-b17b-052261687970" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_019d2478-bcaa-7569-b557-20235d1ab3c0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019d2478-bcaa-79c5-b17b-052261687970" xlink:to="loc_us-gaap_AwardTypeAxis_019d2478-bcaa-7569-b557-20235d1ab3c0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-7569-b557-20235d1ab3c0_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_019d2478-bcaa-7569-b557-20235d1ab3c0" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-7569-b557-20235d1ab3c0_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-7687-840f-fdff89be0e40" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_019d2478-bcaa-7569-b557-20235d1ab3c0" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-7687-840f-fdff89be0e40" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeStockOptionMember_019d2478-bcaa-7591-bd96-16b24f91e68e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeStockOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-7687-840f-fdff89be0e40" xlink:to="loc_us-gaap_EmployeeStockOptionMember_019d2478-bcaa-7591-bd96-16b24f91e68e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_019d2478-bcaa-7684-bb00-51c1f89fb338" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d2478-bcaa-76e7-be96-619c390c917d" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_019d2478-bcaa-7684-bb00-51c1f89fb338" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_019d2478-bcaa-72fe-883a-417e84995de1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_019d2478-bcaa-7684-bb00-51c1f89fb338" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_019d2478-bcaa-72fe-883a-417e84995de1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_019d2478-bcaa-7cc7-bce3-79488530f77e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_019d2478-bcaa-7684-bb00-51c1f89fb338" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_019d2478-bcaa-7cc7-bce3-79488530f77e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_019d2478-bcaa-71cc-9058-3808fc5e8c5a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_019d2478-bcaa-7684-bb00-51c1f89fb338" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_019d2478-bcaa-71cc-9058-3808fc5e8c5a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod_019d2478-bcaa-7714-889c-b41cf9b3639b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_019d2478-bcaa-7684-bb00-51c1f89fb338" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod_019d2478-bcaa-7714-889c-b41cf9b3639b" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_019d2478-bcaa-70e7-93a9-c39e3e989eee" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingNumber_019d2478-bcaa-7d66-91a9-c08abb3fc93c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d2478-bcaa-76e7-be96-619c390c917d" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingNumber_019d2478-bcaa-7d66-91a9-c08abb3fc93c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_019d2478-bcaa-71aa-b21a-251fb5e12d81" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d2478-bcaa-76e7-be96-619c390c917d" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_019d2478-bcaa-71aa-b21a-251fb5e12d81" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_019d2478-bcaa-78a1-a4fd-5540280ac2c6" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_019d2478-bcaa-71aa-b21a-251fb5e12d81" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_019d2478-bcaa-78a1-a4fd-5540280ac2c6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_019d2478-bcaa-76da-aa44-44b855a3cc26" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_019d2478-bcaa-71aa-b21a-251fb5e12d81" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_019d2478-bcaa-76da-aa44-44b855a3cc26" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_019d2478-bcaa-7e8a-b427-0080fad19f28" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_019d2478-bcaa-71aa-b21a-251fb5e12d81" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_019d2478-bcaa-7e8a-b427-0080fad19f28" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice_019d2478-bcaa-70b7-8206-dc4acc53a621" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_019d2478-bcaa-71aa-b21a-251fb5e12d81" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice_019d2478-bcaa-70b7-8206-dc4acc53a621" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_019d2478-bcaa-786e-9cf3-ccf0bbab3294" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageExercisePrice_019d2478-bcaa-7fc4-94ea-98f561744fc2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageExercisePrice"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d2478-bcaa-76e7-be96-619c390c917d" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageExercisePrice_019d2478-bcaa-7fc4-94ea-98f561744fc2" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_019d2478-bcaa-7362-a9c9-6d333e10427a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d2478-bcaa-76e7-be96-619c390c917d" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_019d2478-bcaa-7362-a9c9-6d333e10427a" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_019d2478-bcaa-7b20-b0c4-1b0dc29aaf32" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_019d2478-bcaa-7362-a9c9-6d333e10427a" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_019d2478-bcaa-7b20-b0c4-1b0dc29aaf32" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableAggregateIntrinsicValue_019d2478-bcaa-7b91-9804-e938a898a26d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableAggregateIntrinsicValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_019d2478-bcaa-7362-a9c9-6d333e10427a" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableAggregateIntrinsicValue_019d2478-bcaa-7b91-9804-e938a898a26d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_019d2478-bcaa-7a9d-bd1e-64bed0df6801" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_019d2478-bcaa-7362-a9c9-6d333e10427a" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_019d2478-bcaa-7a9d-bd1e-64bed0df6801" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageRemainingContractualTerm1_019d2478-bcaa-7986-853c-560ccf68b1f9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageRemainingContractualTerm1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_019d2478-bcaa-7362-a9c9-6d333e10427a" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageRemainingContractualTerm1_019d2478-bcaa-7986-853c-560ccf68b1f9" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_019d4377-d2ce-73a3-abe8-ad0e42d9e4ba" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d2478-bcaa-76e7-be96-619c390c917d" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_019d4377-d2ce-73a3-abe8-ad0e42d9e4ba" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.exlservice.com/role/StockBasedCompensationStockOptionsNarrativeDetails" xlink:type="simple" xlink:href="exls-20260331.xsd#StockBasedCompensationStockOptionsNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.exlservice.com/role/StockBasedCompensationStockOptionsNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d2478-bcaa-79c7-86db-d37e830ddf08" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019d2478-bcaa-7976-acab-fc89e3b10207" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d2478-bcaa-79c7-86db-d37e830ddf08" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019d2478-bcaa-7976-acab-fc89e3b10207" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_019d2478-bcaa-7989-b229-74307ae98570" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019d2478-bcaa-7976-acab-fc89e3b10207" xlink:to="loc_us-gaap_AwardTypeAxis_019d2478-bcaa-7989-b229-74307ae98570" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-7989-b229-74307ae98570_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_019d2478-bcaa-7989-b229-74307ae98570" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-7989-b229-74307ae98570_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-76e7-b9bd-5b00a8d9cba4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_019d2478-bcaa-7989-b229-74307ae98570" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-76e7-b9bd-5b00a8d9cba4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeStockOptionMember_019d2478-bcaa-7dd8-b31d-f652e79dcc7d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeStockOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-76e7-b9bd-5b00a8d9cba4" xlink:to="loc_us-gaap_EmployeeStockOptionMember_019d2478-bcaa-7dd8-b31d-f652e79dcc7d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions_019d2478-bcaa-7b09-a5ad-daa8e7e873de" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d2478-bcaa-79c7-86db-d37e830ddf08" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions_019d2478-bcaa-7b09-a5ad-daa8e7e873de" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_019d2478-bcaa-7af8-81fb-c0f9d89fa72a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d2478-bcaa-79c7-86db-d37e830ddf08" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_019d2478-bcaa-7af8-81fb-c0f9d89fa72a" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.exlservice.com/role/StockBasedCompensationShareMatchingProgramNarrativeDetails" xlink:type="simple" xlink:href="exls-20260331.xsd#StockBasedCompensationShareMatchingProgramNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.exlservice.com/role/StockBasedCompensationShareMatchingProgramNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d437e-a56a-7f79-b9d3-863d14039b58" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019d2478-bcaa-7c93-bf46-dde77271b7ab" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d437e-a56a-7f79-b9d3-863d14039b58" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019d2478-bcaa-7c93-bf46-dde77271b7ab" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_019d437e-a56a-794c-b5e9-bf856a9775bc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019d2478-bcaa-7c93-bf46-dde77271b7ab" xlink:to="loc_us-gaap_AwardTypeAxis_019d437e-a56a-794c-b5e9-bf856a9775bc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d437e-a56a-794c-b5e9-bf856a9775bc_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_019d437e-a56a-794c-b5e9-bf856a9775bc" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d437e-a56a-794c-b5e9-bf856a9775bc_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d437e-a56a-7209-9dd4-1c21068f98b5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_019d437e-a56a-794c-b5e9-bf856a9775bc" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d437e-a56a-7209-9dd4-1c21068f98b5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_ShareMatchUnitsMember_019d437e-a56a-7352-b9f5-85774d04e65a" xlink:href="exls-20260331.xsd#exls_ShareMatchUnitsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d437e-a56a-7209-9dd4-1c21068f98b5" xlink:to="loc_exls_ShareMatchUnitsMember_019d437e-a56a-7352-b9f5-85774d04e65a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber_019d437e-a56a-753f-b6dd-1ba88e8fe738" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d437e-a56a-7f79-b9d3-863d14039b58" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber_019d437e-a56a-753f-b6dd-1ba88e8fe738" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.exlservice.com/role/StockBasedCompensationRestrictedStockUnitActivityUnderCompanysStockPlansDetails" xlink:type="simple" xlink:href="exls-20260331.xsd#StockBasedCompensationRestrictedStockUnitActivityUnderCompanysStockPlansDetails"/>
  <link:definitionLink xlink:role="http://www.exlservice.com/role/StockBasedCompensationRestrictedStockUnitActivityUnderCompanysStockPlansDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d2478-bcaa-7f00-b9cb-2e950c10080f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019d2478-bcaa-78a8-9993-a996ec3899a2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d2478-bcaa-7f00-b9cb-2e950c10080f" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019d2478-bcaa-78a8-9993-a996ec3899a2" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_019d2478-bcaa-73b8-b5b5-8cc9a64e57bc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019d2478-bcaa-78a8-9993-a996ec3899a2" xlink:to="loc_us-gaap_AwardTypeAxis_019d2478-bcaa-73b8-b5b5-8cc9a64e57bc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-73b8-b5b5-8cc9a64e57bc_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_019d2478-bcaa-73b8-b5b5-8cc9a64e57bc" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-73b8-b5b5-8cc9a64e57bc_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-703e-9c3d-10d9df5c58b3" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_019d2478-bcaa-73b8-b5b5-8cc9a64e57bc" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-703e-9c3d-10d9df5c58b3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_019d2478-bcaa-79e3-90b2-09e3a22bc0f8" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedStockUnitsRSUMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-703e-9c3d-10d9df5c58b3" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_019d2478-bcaa-79e3-90b2-09e3a22bc0f8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingRollForward_019d2478-bcaa-7603-890b-03decaaa8706" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d2478-bcaa-7f00-b9cb-2e950c10080f" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingRollForward_019d2478-bcaa-7603-890b-03decaaa8706" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_019d2478-bcaa-7daa-9647-760c8e77005d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingRollForward_019d2478-bcaa-7603-890b-03decaaa8706" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_019d2478-bcaa-7daa-9647-760c8e77005d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_019d2478-bcaa-72a1-bb9e-4ca5438b66a7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingRollForward_019d2478-bcaa-7603-890b-03decaaa8706" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_019d2478-bcaa-72a1-bb9e-4ca5438b66a7" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_019d2478-bcaa-7beb-b7fb-d4d4a63b4b7a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingRollForward_019d2478-bcaa-7603-890b-03decaaa8706" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_019d2478-bcaa-7beb-b7fb-d4d4a63b4b7a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_019d2478-bcaa-78ec-9737-1b5c25d4ccd7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingRollForward_019d2478-bcaa-7603-890b-03decaaa8706" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_019d2478-bcaa-78ec-9737-1b5c25d4ccd7" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_019d2478-bcaa-72f0-a929-8a3e6073dbaa" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_019d2478-bcaa-78a5-921f-b8589af3e528" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d2478-bcaa-7f00-b9cb-2e950c10080f" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_019d2478-bcaa-78a5-921f-b8589af3e528" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_019d2478-bcaa-742c-aa63-7c42a3fe1a4b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_019d2478-bcaa-78a5-921f-b8589af3e528" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_019d2478-bcaa-742c-aa63-7c42a3fe1a4b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_019d2478-bcaa-7f4e-b9ac-a9ca30117a8a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_019d2478-bcaa-78a5-921f-b8589af3e528" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_019d2478-bcaa-7f4e-b9ac-a9ca30117a8a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_019d2478-bcaa-74d1-af8a-d2674cf4f8fa" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_019d2478-bcaa-78a5-921f-b8589af3e528" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_019d2478-bcaa-74d1-af8a-d2674cf4f8fa" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_019d2478-bcaa-7f9a-ae19-a4164bde711d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_019d2478-bcaa-78a5-921f-b8589af3e528" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_019d2478-bcaa-7f9a-ae19-a4164bde711d" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_019d2478-bcaa-7e9b-9066-cbffdb25c256" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber_019d2478-bcaa-760e-9b06-3901d83ce475" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d2478-bcaa-7f00-b9cb-2e950c10080f" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber_019d2478-bcaa-760e-9b06-3901d83ce475" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.exlservice.com/role/StockBasedCompensationRestrictedStockUnitNarrativeDetails" xlink:type="simple" xlink:href="exls-20260331.xsd#StockBasedCompensationRestrictedStockUnitNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.exlservice.com/role/StockBasedCompensationRestrictedStockUnitNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d2478-bcaa-761a-904c-b7574efcbdbb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019d2478-bcaa-719e-9811-212231c5d3da" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d2478-bcaa-761a-904c-b7574efcbdbb" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019d2478-bcaa-719e-9811-212231c5d3da" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_019d2478-bcaa-7c00-82f0-e02c55e69048" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019d2478-bcaa-719e-9811-212231c5d3da" xlink:to="loc_us-gaap_AwardTypeAxis_019d2478-bcaa-7c00-82f0-e02c55e69048" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-7c00-82f0-e02c55e69048_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_019d2478-bcaa-7c00-82f0-e02c55e69048" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-7c00-82f0-e02c55e69048_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-7a52-90aa-2e47a9065297" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_019d2478-bcaa-7c00-82f0-e02c55e69048" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-7a52-90aa-2e47a9065297" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_019d2478-bcaa-7f76-b61f-77b43d9b2c49" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedStockUnitsRSUMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-7a52-90aa-2e47a9065297" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_019d2478-bcaa-7f76-b61f-77b43d9b2c49" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions_019d2478-bcaa-7179-9196-263ee24863dd" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d2478-bcaa-761a-904c-b7574efcbdbb" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions_019d2478-bcaa-7179-9196-263ee24863dd" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_019d2478-bcaa-7c6b-bba5-02f986ff6cd1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d2478-bcaa-761a-904c-b7574efcbdbb" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_019d2478-bcaa-7c6b-bba5-02f986ff6cd1" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.exlservice.com/role/StockBasedCompensationPerformanceBasedStockAwardsNarrativeDetails" xlink:type="simple" xlink:href="exls-20260331.xsd#StockBasedCompensationPerformanceBasedStockAwardsNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.exlservice.com/role/StockBasedCompensationPerformanceBasedStockAwardsNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d2478-bcaa-7de6-b548-84b4e79c0703" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019d2478-bcaa-7d75-bb5f-4b124b77f1d2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d2478-bcaa-7de6-b548-84b4e79c0703" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019d2478-bcaa-7d75-bb5f-4b124b77f1d2" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_019d2478-bcaa-7457-9866-6f58285ac86d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019d2478-bcaa-7d75-bb5f-4b124b77f1d2" xlink:to="loc_us-gaap_AwardTypeAxis_019d2478-bcaa-7457-9866-6f58285ac86d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-7457-9866-6f58285ac86d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_019d2478-bcaa-7457-9866-6f58285ac86d" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-7457-9866-6f58285ac86d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-778a-a0f0-20005181dd86" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_019d2478-bcaa-7457-9866-6f58285ac86d" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-778a-a0f0-20005181dd86" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_RevenueBasedPerformanceRestrictedStockUnitsMember_019d2478-bcaa-7bde-9be8-08235f8e9187" xlink:href="exls-20260331.xsd#exls_RevenueBasedPerformanceRestrictedStockUnitsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-778a-a0f0-20005181dd86" xlink:to="loc_exls_RevenueBasedPerformanceRestrictedStockUnitsMember_019d2478-bcaa-7bde-9be8-08235f8e9187" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_MarketConditionBasedPerformanceRestrictedStockUnitsMember_019d2478-bcaa-7b95-b945-48b2d2b8a166" xlink:href="exls-20260331.xsd#exls_MarketConditionBasedPerformanceRestrictedStockUnitsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-778a-a0f0-20005181dd86" xlink:to="loc_exls_MarketConditionBasedPerformanceRestrictedStockUnitsMember_019d2478-bcaa-7b95-b945-48b2d2b8a166" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_PerformanceBasedStockAwardsMember_019d2478-bcaa-7220-b956-b34e8467cdf1" xlink:href="exls-20260331.xsd#exls_PerformanceBasedStockAwardsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-778a-a0f0-20005181dd86" xlink:to="loc_exls_PerformanceBasedStockAwardsMember_019d2478-bcaa-7220-b956-b34e8467cdf1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameAxis_019d2478-bcaa-7bd5-b3df-46f5100228bb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019d2478-bcaa-7d75-bb5f-4b124b77f1d2" xlink:to="loc_us-gaap_PlanNameAxis_019d2478-bcaa-7bd5-b3df-46f5100228bb" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameDomain_019d2478-bcaa-7bd5-b3df-46f5100228bb_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PlanNameAxis_019d2478-bcaa-7bd5-b3df-46f5100228bb" xlink:to="loc_us-gaap_PlanNameDomain_019d2478-bcaa-7bd5-b3df-46f5100228bb_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameDomain_019d2478-bcaa-7c7f-8523-aa8f3d82e94d" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PlanNameAxis_019d2478-bcaa-7bd5-b3df-46f5100228bb" xlink:to="loc_us-gaap_PlanNameDomain_019d2478-bcaa-7c7f-8523-aa8f3d82e94d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_AmendmentAndRestatementOfThe2006OmnibusAwardPlan2015PlanMember_019d2478-bcaa-78f9-9383-f06bdd84ae5a" xlink:href="exls-20260331.xsd#exls_AmendmentAndRestatementOfThe2006OmnibusAwardPlan2015PlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PlanNameDomain_019d2478-bcaa-7c7f-8523-aa8f3d82e94d" xlink:to="loc_exls_AmendmentAndRestatementOfThe2006OmnibusAwardPlan2015PlanMember_019d2478-bcaa-78f9-9383-f06bdd84ae5a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_PercentageOfPerformanceCriteriaAchievedAndSharesVested_019d2478-bcaa-730a-8f59-014314d00e8f" xlink:href="exls-20260331.xsd#exls_PercentageOfPerformanceCriteriaAchievedAndSharesVested"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d2478-bcaa-7de6-b548-84b4e79c0703" xlink:to="loc_exls_PercentageOfPerformanceCriteriaAchievedAndSharesVested_019d2478-bcaa-730a-8f59-014314d00e8f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_019d2478-bcaa-7ac6-803d-e74259740ddb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d2478-bcaa-7de6-b548-84b4e79c0703" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_019d2478-bcaa-7ac6-803d-e74259740ddb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions_019d2478-bcaa-71d5-b984-c24635dea3a9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d2478-bcaa-7de6-b548-84b4e79c0703" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions_019d2478-bcaa-71d5-b984-c24635dea3a9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_019d2478-bcaa-7ec8-a766-cdc293824ab7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d2478-bcaa-7de6-b548-84b4e79c0703" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_019d2478-bcaa-7ec8-a766-cdc293824ab7" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.exlservice.com/role/StockBasedCompensationPerformanceRestrictedStockActivityDetails" xlink:type="simple" xlink:href="exls-20260331.xsd#StockBasedCompensationPerformanceRestrictedStockActivityDetails"/>
  <link:definitionLink xlink:role="http://www.exlservice.com/role/StockBasedCompensationPerformanceRestrictedStockActivityDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d2478-bcaa-70c4-9159-aa6128676497" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019d2478-bcaa-7960-91be-fb1d333469b5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d2478-bcaa-70c4-9159-aa6128676497" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019d2478-bcaa-7960-91be-fb1d333469b5" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_019d2478-bcaa-7abe-9a07-793b5931d3bb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019d2478-bcaa-7960-91be-fb1d333469b5" xlink:to="loc_us-gaap_AwardTypeAxis_019d2478-bcaa-7abe-9a07-793b5931d3bb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-7abe-9a07-793b5931d3bb_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_019d2478-bcaa-7abe-9a07-793b5931d3bb" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-7abe-9a07-793b5931d3bb_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-7077-aa8e-f63dcdf5ee4f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_019d2478-bcaa-7abe-9a07-793b5931d3bb" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-7077-aa8e-f63dcdf5ee4f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_RevenueBasedPerformanceRestrictedStockUnitsMember_019d2478-bcaa-7d35-acbe-fc8b9c0770cb" xlink:href="exls-20260331.xsd#exls_RevenueBasedPerformanceRestrictedStockUnitsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-7077-aa8e-f63dcdf5ee4f" xlink:to="loc_exls_RevenueBasedPerformanceRestrictedStockUnitsMember_019d2478-bcaa-7d35-acbe-fc8b9c0770cb" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_MarketConditionBasedPerformanceRestrictedStockUnitsMember_019d2478-bcaa-77af-90d7-e1f083bee342" xlink:href="exls-20260331.xsd#exls_MarketConditionBasedPerformanceRestrictedStockUnitsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-7077-aa8e-f63dcdf5ee4f" xlink:to="loc_exls_MarketConditionBasedPerformanceRestrictedStockUnitsMember_019d2478-bcaa-77af-90d7-e1f083bee342" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingRollForward_019d2478-bcaa-7a1c-984c-55112a8887ff" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d2478-bcaa-70c4-9159-aa6128676497" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingRollForward_019d2478-bcaa-7a1c-984c-55112a8887ff" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_019d2478-bcaa-7566-a0bb-0d83acede6b1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingRollForward_019d2478-bcaa-7a1c-984c-55112a8887ff" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_019d2478-bcaa-7566-a0bb-0d83acede6b1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_019d2478-bcaa-7197-a6e2-941071eb54b9" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingRollForward_019d2478-bcaa-7a1c-984c-55112a8887ff" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_019d2478-bcaa-7197-a6e2-941071eb54b9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_019d2478-bcaa-7525-8277-09215a8d8976" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingRollForward_019d2478-bcaa-7a1c-984c-55112a8887ff" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_019d2478-bcaa-7525-8277-09215a8d8976" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_019d2478-bcaa-7821-90d6-76373872f767" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingRollForward_019d2478-bcaa-7a1c-984c-55112a8887ff" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_019d2478-bcaa-7821-90d6-76373872f767" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_019d2478-bcaa-766a-8d76-c97180abb8cb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_019d2478-bcaa-76fb-92dc-46112c47710c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d2478-bcaa-70c4-9159-aa6128676497" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_019d2478-bcaa-76fb-92dc-46112c47710c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_019d2478-bcaa-7cc6-9265-ea2190b59ed5" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_019d2478-bcaa-76fb-92dc-46112c47710c" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_019d2478-bcaa-7cc6-9265-ea2190b59ed5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_019d2478-bcaa-7317-892d-934b62cd3edb" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_019d2478-bcaa-76fb-92dc-46112c47710c" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_019d2478-bcaa-7317-892d-934b62cd3edb" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_019d2478-bcaa-70bf-8dac-75cf4a703865" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_019d2478-bcaa-76fb-92dc-46112c47710c" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_019d2478-bcaa-70bf-8dac-75cf4a703865" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_019d2478-bcaa-7e7f-a91e-4554ecbb5ee4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_019d2478-bcaa-76fb-92dc-46112c47710c" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_019d2478-bcaa-7e7f-a91e-4554ecbb5ee4" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_019d2478-bcaa-7618-9bcb-6b6771426132" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.exlservice.com/role/StockBasedCompensationEmployeeStockPurchasePlanNarrativeDetails" xlink:type="simple" xlink:href="exls-20260331.xsd#StockBasedCompensationEmployeeStockPurchasePlanNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.exlservice.com/role/StockBasedCompensationEmployeeStockPurchasePlanNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeStockOwnershipPlanESOPDisclosuresLineItems_019d2478-bcaa-7cae-8c54-ca56451edabc" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeStockOwnershipPlanESOPDisclosuresLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEmployeeStockOwnershipPlanESOPDisclosuresTable_019d2478-bcaa-758f-9c66-4470a79015ad" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfEmployeeStockOwnershipPlanESOPDisclosuresTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_EmployeeStockOwnershipPlanESOPDisclosuresLineItems_019d2478-bcaa-7cae-8c54-ca56451edabc" xlink:to="loc_us-gaap_ScheduleOfEmployeeStockOwnershipPlanESOPDisclosuresTable_019d2478-bcaa-758f-9c66-4470a79015ad" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_019d2478-bcaa-7b57-8a86-6c21261ae55b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEmployeeStockOwnershipPlanESOPDisclosuresTable_019d2478-bcaa-758f-9c66-4470a79015ad" xlink:to="loc_us-gaap_AwardTypeAxis_019d2478-bcaa-7b57-8a86-6c21261ae55b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-7b57-8a86-6c21261ae55b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_019d2478-bcaa-7b57-8a86-6c21261ae55b" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-7b57-8a86-6c21261ae55b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-7576-b802-3da9fc798a46" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_019d2478-bcaa-7b57-8a86-6c21261ae55b" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-7576-b802-3da9fc798a46" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeStockMember_019d2478-bcaa-7f74-b98d-1c3ce83fa028" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-7576-b802-3da9fc798a46" xlink:to="loc_us-gaap_EmployeeStockMember_019d2478-bcaa-7f74-b98d-1c3ce83fa028" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameAxis_019d2478-bcaa-7099-8636-24d3a1312323" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEmployeeStockOwnershipPlanESOPDisclosuresTable_019d2478-bcaa-758f-9c66-4470a79015ad" xlink:to="loc_us-gaap_PlanNameAxis_019d2478-bcaa-7099-8636-24d3a1312323" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameDomain_019d2478-bcaa-7099-8636-24d3a1312323_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PlanNameAxis_019d2478-bcaa-7099-8636-24d3a1312323" xlink:to="loc_us-gaap_PlanNameDomain_019d2478-bcaa-7099-8636-24d3a1312323_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameDomain_019d2478-bcaa-73d7-a509-f9252b846156" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PlanNameAxis_019d2478-bcaa-7099-8636-24d3a1312323" xlink:to="loc_us-gaap_PlanNameDomain_019d2478-bcaa-73d7-a509-f9252b846156" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_A2022EmployeeStockPurchasePlanMember_019d2478-bcaa-73cb-8db2-af0c4196b26d" xlink:href="exls-20260331.xsd#exls_A2022EmployeeStockPurchasePlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PlanNameDomain_019d2478-bcaa-73d7-a509-f9252b846156" xlink:to="loc_exls_A2022EmployeeStockPurchasePlanMember_019d2478-bcaa-73cb-8db2-af0c4196b26d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumEmployeeSubscriptionRate_019d2478-bcaa-7866-b099-223ef5bbe849" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumEmployeeSubscriptionRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EmployeeStockOwnershipPlanESOPDisclosuresLineItems_019d2478-bcaa-7cae-8c54-ca56451edabc" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumEmployeeSubscriptionRate_019d2478-bcaa-7866-b099-223ef5bbe849" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumEmployeeSubscription_019d2478-bcaa-7823-8b93-6bd951e549a7" xlink:href="exls-20260331.xsd#exls_ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumEmployeeSubscription"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EmployeeStockOwnershipPlanESOPDisclosuresLineItems_019d2478-bcaa-7cae-8c54-ca56451edabc" xlink:to="loc_exls_ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumEmployeeSubscription_019d2478-bcaa-7823-8b93-6bd951e549a7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_019d2478-bcaa-7292-852a-1194b9c86439" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockCapitalSharesReservedForFutureIssuance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EmployeeStockOwnershipPlanESOPDisclosuresLineItems_019d2478-bcaa-7cae-8c54-ca56451edabc" xlink:to="loc_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_019d2478-bcaa-7292-852a-1194b9c86439" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_ShareBasedCompensationArrangementByShareBasedPaymentAwardPurchasePeriod_019d2478-bcaa-7c63-a3eb-ef40373e0d74" xlink:href="exls-20260331.xsd#exls_ShareBasedCompensationArrangementByShareBasedPaymentAwardPurchasePeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EmployeeStockOwnershipPlanESOPDisclosuresLineItems_019d2478-bcaa-7cae-8c54-ca56451edabc" xlink:to="loc_exls_ShareBasedCompensationArrangementByShareBasedPaymentAwardPurchasePeriod_019d2478-bcaa-7c63-a3eb-ef40373e0d74" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.exlservice.com/role/StockBasedCompensationScheduleofShareBasedCompensationEmployeeStockPurchaseActivityDetails" xlink:type="simple" xlink:href="exls-20260331.xsd#StockBasedCompensationScheduleofShareBasedCompensationEmployeeStockPurchaseActivityDetails"/>
  <link:definitionLink xlink:role="http://www.exlservice.com/role/StockBasedCompensationScheduleofShareBasedCompensationEmployeeStockPurchaseActivityDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d2478-bcaa-7df7-b61a-146b6498a46a" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019d2478-bcaa-7a3a-8ca8-8ae3cde0ecf7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d2478-bcaa-7df7-b61a-146b6498a46a" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019d2478-bcaa-7a3a-8ca8-8ae3cde0ecf7" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_019d2478-bcaa-7d83-a7d2-c3acf58db1ee" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019d2478-bcaa-7a3a-8ca8-8ae3cde0ecf7" xlink:to="loc_us-gaap_AwardTypeAxis_019d2478-bcaa-7d83-a7d2-c3acf58db1ee" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-7d83-a7d2-c3acf58db1ee_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_019d2478-bcaa-7d83-a7d2-c3acf58db1ee" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-7d83-a7d2-c3acf58db1ee_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-7beb-8154-591f8d1325e7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_019d2478-bcaa-7d83-a7d2-c3acf58db1ee" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-7beb-8154-591f8d1325e7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeStockMember_019d2478-bcaa-7867-a70c-5aabe9dc8743" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019d2478-bcaa-7beb-8154-591f8d1325e7" xlink:to="loc_us-gaap_EmployeeStockMember_019d2478-bcaa-7867-a70c-5aabe9dc8743" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameAxis_019d2478-bcaa-7e8a-9916-3762c6f8f0e4" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019d2478-bcaa-7a3a-8ca8-8ae3cde0ecf7" xlink:to="loc_us-gaap_PlanNameAxis_019d2478-bcaa-7e8a-9916-3762c6f8f0e4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameDomain_019d2478-bcaa-7e8a-9916-3762c6f8f0e4_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PlanNameAxis_019d2478-bcaa-7e8a-9916-3762c6f8f0e4" xlink:to="loc_us-gaap_PlanNameDomain_019d2478-bcaa-7e8a-9916-3762c6f8f0e4_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameDomain_019d2478-bcaa-7737-bded-a22fe7f9785e" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PlanNameAxis_019d2478-bcaa-7e8a-9916-3762c6f8f0e4" xlink:to="loc_us-gaap_PlanNameDomain_019d2478-bcaa-7737-bded-a22fe7f9785e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_A2022EmployeeStockPurchasePlanMember_019d2478-bcaa-7f29-8a60-d8bd1e445ad1" xlink:href="exls-20260331.xsd#exls_A2022EmployeeStockPurchasePlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PlanNameDomain_019d2478-bcaa-7737-bded-a22fe7f9785e" xlink:to="loc_exls_A2022EmployeeStockPurchasePlanMember_019d2478-bcaa-7f29-8a60-d8bd1e445ad1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_019d2478-bcaa-7d52-8edb-e6d4617a2adf" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockCapitalSharesReservedForFutureIssuance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d2478-bcaa-7df7-b61a-146b6498a46a" xlink:to="loc_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_019d2478-bcaa-7d52-8edb-e6d4617a2adf" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod_019d2478-bcaa-7679-9512-004c7bb70b4b" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d2478-bcaa-7df7-b61a-146b6498a46a" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod_019d2478-bcaa-7679-9512-004c7bb70b4b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan_019d2478-bcaa-7e6d-ab2c-7ea9634e91f7" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d2478-bcaa-7df7-b61a-146b6498a46a" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan_019d2478-bcaa-7e6d-ab2c-7ea9634e91f7" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredCompensationSharebasedArrangementsLiabilityCurrentAndNoncurrent_019d2478-bcaa-782b-b2b5-9db11e4e04f1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DeferredCompensationSharebasedArrangementsLiabilityCurrentAndNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019d2478-bcaa-7df7-b61a-146b6498a46a" xlink:to="loc_us-gaap_DeferredCompensationSharebasedArrangementsLiabilityCurrentAndNoncurrent_019d2478-bcaa-782b-b2b5-9db11e4e04f1" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.exlservice.com/role/RelatedPartyDisclosuresDetails" xlink:type="simple" xlink:href="exls-20260331.xsd#RelatedPartyDisclosuresDetails"/>
  <link:definitionLink xlink:role="http://www.exlservice.com/role/RelatedPartyDisclosuresDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionLineItems_019d2478-bcaa-703d-91a7-d0178d5770b0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_019d2478-bcaa-7906-8f75-c14a389ee47f" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019d2478-bcaa-703d-91a7-d0178d5770b0" xlink:to="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_019d2478-bcaa-7906-8f75-c14a389ee47f" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019d2478-bcaa-737e-84ee-13a24f4946be" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_019d2478-bcaa-7906-8f75-c14a389ee47f" xlink:to="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019d2478-bcaa-737e-84ee-13a24f4946be" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_019d2478-bcaa-737e-84ee-13a24f4946be_default" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019d2478-bcaa-737e-84ee-13a24f4946be" xlink:to="loc_us-gaap_RelatedPartyDomain_019d2478-bcaa-737e-84ee-13a24f4946be_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_019d2478-bcaa-7197-97df-a26e360bff9c" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019d2478-bcaa-737e-84ee-13a24f4946be" xlink:to="loc_us-gaap_RelatedPartyDomain_019d2478-bcaa-7197-97df-a26e360bff9c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyMember_019d2478-bcaa-7213-8c52-9bd291c8b129" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_019d2478-bcaa-7197-97df-a26e360bff9c" xlink:to="loc_us-gaap_RelatedPartyMember_019d2478-bcaa-7213-8c52-9bd291c8b129" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CounterpartyNameAxis_019d2478-bcaa-7845-9239-8d37119d1cd4" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_CounterpartyNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_019d2478-bcaa-7906-8f75-c14a389ee47f" xlink:to="loc_srt_CounterpartyNameAxis_019d2478-bcaa-7845-9239-8d37119d1cd4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019d2478-bcaa-7845-9239-8d37119d1cd4_default" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_CounterpartyNameAxis_019d2478-bcaa-7845-9239-8d37119d1cd4" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019d2478-bcaa-7845-9239-8d37119d1cd4_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019d2478-bcaa-793e-876b-280a7ae27c76" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_CounterpartyNameAxis_019d2478-bcaa-7845-9239-8d37119d1cd4" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019d2478-bcaa-793e-876b-280a7ae27c76" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_exls_CorridorPlatformsIncMember_019d2478-bcaa-785b-92dc-20310db1e08b" xlink:href="exls-20260331.xsd#exls_CorridorPlatformsIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019d2478-bcaa-793e-876b-280a7ae27c76" xlink:to="loc_exls_CorridorPlatformsIncMember_019d2478-bcaa-785b-92dc-20310db1e08b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_019d2478-bcaa-73d8-892e-1b1dc15e71be" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019d2478-bcaa-703d-91a7-d0178d5770b0" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_019d2478-bcaa-73d8-892e-1b1dc15e71be" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsReceivableNetCurrent_019d2478-bcaa-7ad1-982e-d7482f5ffef0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsReceivableNetCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019d2478-bcaa-703d-91a7-d0178d5770b0" xlink:to="loc_us-gaap_AccountsReceivableNetCurrent_019d2478-bcaa-7ad1-982e-d7482f5ffef0" xlink:type="arc" order="1"/>
  </link:definitionLink>
</link:linkbase>
