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

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2026 Workiva-->
<!--r:019ebe77-39bf-7987-96b6-49e2081ad70f,g:d6b42f00-97a3-4fb6-a556-e936139afb40-->
<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.fabrinet.com/role/CONSOLIDATEDSTATEMENTSOFSHAREHOLDERSEQUITY" xlink:type="simple" xlink:href="fn-20260626.xsd#CONSOLIDATEDSTATEMENTSOFSHAREHOLDERSEQUITY"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/CONSOLIDATEDSTATEMENTSOFSHAREHOLDERSEQUITY" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_019ebe77-3c2c-7b62-84aa-5f6270bba5a1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_019ebe77-3c2c-7a8f-a4d1-ef0c3c5442a8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_019ebe77-3c2c-7b62-84aa-5f6270bba5a1" xlink:to="loc_us-gaap_StatementTable_019ebe77-3c2c-7a8f-a4d1-ef0c3c5442a8" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_019ebe77-3c2c-71ad-b088-53d74f00870f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_019ebe77-3c2c-7a8f-a4d1-ef0c3c5442a8" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_019ebe77-3c2c-71ad-b088-53d74f00870f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_019ebe77-3c2c-71ad-b088-53d74f00870f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_019ebe77-3c2c-71ad-b088-53d74f00870f" xlink:to="loc_us-gaap_EquityComponentDomain_019ebe77-3c2c-71ad-b088-53d74f00870f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_019ebe77-3c2c-7983-a961-0b8c2b37c11c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_019ebe77-3c2c-71ad-b088-53d74f00870f" xlink:to="loc_us-gaap_EquityComponentDomain_019ebe77-3c2c-7983-a961-0b8c2b37c11c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockMember_019ebe77-3c2c-724d-9c18-11c5e49dcf87" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019ebe77-3c2c-7983-a961-0b8c2b37c11c" xlink:to="loc_us-gaap_CommonStockMember_019ebe77-3c2c-724d-9c18-11c5e49dcf87" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalPaidInCapitalMember_019ebe77-3c2c-7a7a-9e54-f25e75f5a211" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdditionalPaidInCapitalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019ebe77-3c2c-7983-a961-0b8c2b37c11c" xlink:to="loc_us-gaap_AdditionalPaidInCapitalMember_019ebe77-3c2c-7a7a-9e54-f25e75f5a211" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockCommonMember_019ebe77-3c2c-70e2-a403-f11f94684739" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TreasuryStockCommonMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019ebe77-3c2c-7983-a961-0b8c2b37c11c" xlink:to="loc_us-gaap_TreasuryStockCommonMember_019ebe77-3c2c-70e2-a403-f11f94684739" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_019ebe77-3c2c-78f0-a14c-54149c99c4df" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019ebe77-3c2c-7983-a961-0b8c2b37c11c" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_019ebe77-3c2c-78f0-a14c-54149c99c4df" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsMember_019ebe77-3c2c-765b-ab4b-0bf42f38a6ac" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RetainedEarningsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019ebe77-3c2c-7983-a961-0b8c2b37c11c" xlink:to="loc_us-gaap_RetainedEarningsMember_019ebe77-3c2c-765b-ab4b-0bf42f38a6ac" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019ebe77-3c2c-7134-bda9-c50997ef0da6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInStockholdersEquityRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ebe77-3c2c-7b62-84aa-5f6270bba5a1" xlink:to="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019ebe77-3c2c-7134-bda9-c50997ef0da6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharesOutstanding_019ebe77-3c2c-7ebc-9daf-b373ad356869" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019ebe77-3c2c-7134-bda9-c50997ef0da6" xlink:to="loc_us-gaap_SharesOutstanding_019ebe77-3c2c-7ebc-9daf-b373ad356869" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_019ebe77-3c2c-749e-89b1-52d7bd36837a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019ebe77-3c2c-7134-bda9-c50997ef0da6" xlink:to="loc_us-gaap_StockholdersEquity_019ebe77-3c2c-749e-89b1-52d7bd36837a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_019ebe77-3c2c-7d13-b2ca-b205cd518746" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019ebe77-3c2c-7134-bda9-c50997ef0da6" xlink:to="loc_us-gaap_NetIncomeLoss_019ebe77-3c2c-7d13-b2ca-b205cd518746" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_019ebe77-3c2c-7057-9ae5-7de97c746ee5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019ebe77-3c2c-7134-bda9-c50997ef0da6" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_019ebe77-3c2c-7057-9ae5-7de97c746ee5" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_019ebe77-3c2c-771c-b550-6c7c12acc7d8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019ebe77-3c2c-7134-bda9-c50997ef0da6" xlink:to="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_019ebe77-3c2c-771c-b550-6c7c12acc7d8" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalWarrantIssued_019ebe77-3c2c-7281-8cec-6178a65b4079" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalWarrantIssued"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019ebe77-3c2c-7134-bda9-c50997ef0da6" xlink:to="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalWarrantIssued_019ebe77-3c2c-7281-8cec-6178a65b4079" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation_019ebe77-3c2c-739c-8b07-d33a88778022" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019ebe77-3c2c-7134-bda9-c50997ef0da6" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation_019ebe77-3c2c-739c-8b07-d33a88778022" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation_019ebe77-3c2c-717c-8b71-1f510aa62a0a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019ebe77-3c2c-7134-bda9-c50997ef0da6" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation_019ebe77-3c2c-717c-8b71-1f510aa62a0a" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockValueAcquiredCostMethod_019ebe77-3c2c-7134-9ecf-16ebfe4f6ab4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TreasuryStockValueAcquiredCostMethod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019ebe77-3c2c-7134-bda9-c50997ef0da6" xlink:to="loc_us-gaap_TreasuryStockValueAcquiredCostMethod_019ebe77-3c2c-7134-9ecf-16ebfe4f6ab4" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation_019ebe77-3c2c-73b8-9b57-2a71f1cf64b6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019ebe77-3c2c-7134-bda9-c50997ef0da6" xlink:to="loc_us-gaap_AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation_019ebe77-3c2c-73b8-9b57-2a71f1cf64b6" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharesOutstanding_019ebe77-3c2c-751c-aad8-e97c2e5bbd29" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SharesOutstanding"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_019ebe77-3c2c-7210-ad89-e0e894a9a6ba" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquity"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/SummaryofsignificantaccountingpoliciesScheduleofPropertyPlantandEquipmentEstimatedUsefulLifeDetails" xlink:type="simple" xlink:href="fn-20260626.xsd#SummaryofsignificantaccountingpoliciesScheduleofPropertyPlantandEquipmentEstimatedUsefulLifeDetails"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/SummaryofsignificantaccountingpoliciesScheduleofPropertyPlantandEquipmentEstimatedUsefulLifeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_019ebe77-3c2d-7a3d-b000-3b1b2c7ca4b7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_019ebe77-3c2d-7ba1-a459-ad6c1daa42c1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfPropertyPlantAndEquipmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_019ebe77-3c2d-7a3d-b000-3b1b2c7ca4b7" xlink:to="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_019ebe77-3c2d-7ba1-a459-ad6c1daa42c1" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_019ebe77-3c2d-7fb2-b169-a105358c1f2b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentByTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_019ebe77-3c2d-7ba1-a459-ad6c1daa42c1" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_019ebe77-3c2d-7fb2-b169-a105358c1f2b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019ebe77-3c2d-7fb2-b169-a105358c1f2b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_019ebe77-3c2d-7fb2-b169-a105358c1f2b" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019ebe77-3c2d-7fb2-b169-a105358c1f2b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019ebe77-3c2d-7483-a5b6-f6a8b7a8c31b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_019ebe77-3c2d-7fb2-b169-a105358c1f2b" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019ebe77-3c2d-7483-a5b6-f6a8b7a8c31b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LandImprovementsMember_019ebe77-3c2d-74af-ab16-8537c89fc4f0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LandImprovementsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019ebe77-3c2d-7483-a5b6-f6a8b7a8c31b" xlink:to="loc_us-gaap_LandImprovementsMember_019ebe77-3c2d-74af-ab16-8537c89fc4f0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BuildingAndBuildingImprovementsMember_019ebe77-3c2d-7310-a78a-6295f6bd8b74" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BuildingAndBuildingImprovementsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019ebe77-3c2d-7483-a5b6-f6a8b7a8c31b" xlink:to="loc_us-gaap_BuildingAndBuildingImprovementsMember_019ebe77-3c2d-7310-a78a-6295f6bd8b74" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquipmentMember_019ebe77-3c2d-7415-abb9-3acf4265cee9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquipmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019ebe77-3c2d-7483-a5b6-f6a8b7a8c31b" xlink:to="loc_us-gaap_EquipmentMember_019ebe77-3c2d-7415-abb9-3acf4265cee9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OfficeEquipmentMember_019ebe77-3c2d-7f0c-8cd5-fb3a368a055d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OfficeEquipmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019ebe77-3c2d-7483-a5b6-f6a8b7a8c31b" xlink:to="loc_us-gaap_OfficeEquipmentMember_019ebe77-3c2d-7f0c-8cd5-fb3a368a055d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VehiclesMember_019ebe77-3c2d-726c-9df3-9a81ae44689d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VehiclesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019ebe77-3c2d-7483-a5b6-f6a8b7a8c31b" xlink:to="loc_us-gaap_VehiclesMember_019ebe77-3c2d-726c-9df3-9a81ae44689d" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComputerEquipmentMember_019ebe77-3c2d-732c-a670-a392fa6a9837" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ComputerEquipmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019ebe77-3c2d-7483-a5b6-f6a8b7a8c31b" xlink:to="loc_us-gaap_ComputerEquipmentMember_019ebe77-3c2d-732c-a670-a392fa6a9837" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_019ebe77-3c2d-7237-a244-69e6be611e58" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_019ebe77-3c2d-7ba1-a459-ad6c1daa42c1" xlink:to="loc_srt_RangeAxis_019ebe77-3c2d-7237-a244-69e6be611e58" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019ebe77-3c2d-7237-a244-69e6be611e58_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_019ebe77-3c2d-7237-a244-69e6be611e58" xlink:to="loc_srt_RangeMember_019ebe77-3c2d-7237-a244-69e6be611e58_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019ebe77-3c2d-7a54-a621-e892673ad22a" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_019ebe77-3c2d-7237-a244-69e6be611e58" xlink:to="loc_srt_RangeMember_019ebe77-3c2d-7a54-a621-e892673ad22a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_019ebe77-3c2d-70e5-af16-781ea51095af" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019ebe77-3c2d-7a54-a621-e892673ad22a" xlink:to="loc_srt_MinimumMember_019ebe77-3c2d-70e5-af16-781ea51095af" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_019ebe77-3c2d-7443-b968-dc0a00ae53eb" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019ebe77-3c2d-7a54-a621-e892673ad22a" xlink:to="loc_srt_MaximumMember_019ebe77-3c2d-7443-b968-dc0a00ae53eb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentUsefulLife_019ebe77-3c2d-7d57-966b-bd1e9bccf044" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentUsefulLife"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ebe77-3c2d-7a3d-b000-3b1b2c7ca4b7" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentUsefulLife_019ebe77-3c2d-7d57-966b-bd1e9bccf044" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/SummaryofsignificantaccountingpoliciesAdditionalInformationDetails" xlink:type="simple" xlink:href="fn-20260626.xsd#SummaryofsignificantaccountingpoliciesAdditionalInformationDetails"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/SummaryofsignificantaccountingpoliciesAdditionalInformationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_fn_AccountingPoliciesLineItems_019ebe77-3c2d-762f-a3e7-3fed83aded12" xlink:href="fn-20260626.xsd#fn_AccountingPoliciesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_AccountingPoliciesTable_019ebe77-3c2d-74e6-b399-954315545974" xlink:href="fn-20260626.xsd#fn_AccountingPoliciesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_fn_AccountingPoliciesLineItems_019ebe77-3c2d-762f-a3e7-3fed83aded12" xlink:to="loc_fn_AccountingPoliciesTable_019ebe77-3c2d-74e6-b399-954315545974" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_019ebe77-3c2d-7a5b-9ff4-500c375aa2a8" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_fn_AccountingPoliciesTable_019ebe77-3c2d-74e6-b399-954315545974" xlink:to="loc_srt_RangeAxis_019ebe77-3c2d-7a5b-9ff4-500c375aa2a8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019ebe77-3c2d-7a5b-9ff4-500c375aa2a8_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_019ebe77-3c2d-7a5b-9ff4-500c375aa2a8" xlink:to="loc_srt_RangeMember_019ebe77-3c2d-7a5b-9ff4-500c375aa2a8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019ebe77-3c2d-7f7f-93e2-c00e85991efc" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_019ebe77-3c2d-7a5b-9ff4-500c375aa2a8" xlink:to="loc_srt_RangeMember_019ebe77-3c2d-7f7f-93e2-c00e85991efc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_019ebe77-3c2d-70df-aab8-69509cd711fd" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019ebe77-3c2d-7f7f-93e2-c00e85991efc" xlink:to="loc_srt_MinimumMember_019ebe77-3c2d-70df-aab8-69509cd711fd" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_019ebe77-3c2d-7ee4-bb1f-4e58c69a461d" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019ebe77-3c2d-7f7f-93e2-c00e85991efc" xlink:to="loc_srt_MaximumMember_019ebe77-3c2d-7ee4-bb1f-4e58c69a461d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_ProductWarrantyTerm_019ebe77-3c2d-7b97-b5f0-a009681f2bc4" xlink:href="fn-20260626.xsd#fn_ProductWarrantyTerm"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_AccountingPoliciesLineItems_019ebe77-3c2d-762f-a3e7-3fed83aded12" xlink:to="loc_fn_ProductWarrantyTerm_019ebe77-3c2d-7b97-b5f0-a009681f2bc4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_ServiceRevenue_019ebe77-3c2d-7b88-a5ac-53e9dea076ab" xlink:href="fn-20260626.xsd#fn_ServiceRevenue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_AccountingPoliciesLineItems_019ebe77-3c2d-762f-a3e7-3fed83aded12" xlink:to="loc_fn_ServiceRevenue_019ebe77-3c2d-7b88-a5ac-53e9dea076ab" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StandardProductWarrantyAccrualWarrantiesIssued_019fa20c-1ee0-7cbd-b130-936da083ac0e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StandardProductWarrantyAccrualWarrantiesIssued"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_AccountingPoliciesLineItems_019ebe77-3c2d-762f-a3e7-3fed83aded12" xlink:to="loc_us-gaap_StandardProductWarrantyAccrualWarrantiesIssued_019fa20c-1ee0-7cbd-b130-936da083ac0e" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/RevenuesfromcontractswithcustomersScheduleofDisaggregationofRevenuebyGeographicalRegionsDetails" xlink:type="simple" xlink:href="fn-20260626.xsd#RevenuesfromcontractswithcustomersScheduleofDisaggregationofRevenuebyGeographicalRegionsDetails"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/RevenuesfromcontractswithcustomersScheduleofDisaggregationofRevenuebyGeographicalRegionsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_019ebe77-3c2d-79a3-927e-b2eb1b7ec3bc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueTable_019ebe77-3c2d-7bd9-bd90-17e8a71d923a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisaggregationOfRevenueTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_019ebe77-3c2d-79a3-927e-b2eb1b7ec3bc" xlink:to="loc_us-gaap_DisaggregationOfRevenueTable_019ebe77-3c2d-7bd9-bd90-17e8a71d923a" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_019ebe77-3c2d-708b-8fcb-2a02ffa0e6f5" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_019ebe77-3c2d-7bd9-bd90-17e8a71d923a" xlink:to="loc_srt_StatementGeographicalAxis_019ebe77-3c2d-708b-8fcb-2a02ffa0e6f5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_019ebe77-3c2d-708b-8fcb-2a02ffa0e6f5_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_019ebe77-3c2d-708b-8fcb-2a02ffa0e6f5" xlink:to="loc_srt_SegmentGeographicalDomain_019ebe77-3c2d-708b-8fcb-2a02ffa0e6f5_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_019ebe77-3c2d-7fed-a4be-0ae32fc814d6" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_019ebe77-3c2d-708b-8fcb-2a02ffa0e6f5" xlink:to="loc_srt_SegmentGeographicalDomain_019ebe77-3c2d-7fed-a4be-0ae32fc814d6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_AsiaPacificMember_019ebe77-3c2d-7f2b-9893-b12699300422" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_AsiaPacificMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_019ebe77-3c2d-7fed-a4be-0ae32fc814d6" xlink:to="loc_srt_AsiaPacificMember_019ebe77-3c2d-7f2b-9893-b12699300422" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_TH_019ebe77-3c2d-7f4b-b40f-610db32c4d9a" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_TH"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_AsiaPacificMember_019ebe77-3c2d-7f2b-9893-b12699300422" xlink:to="loc_country_TH_019ebe77-3c2d-7f4b-b40f-610db32c4d9a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_SG_019ebe77-3c2d-799d-acbb-79399e18bcd5" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_SG"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_AsiaPacificMember_019ebe77-3c2d-7f2b-9893-b12699300422" xlink:to="loc_country_SG_019ebe77-3c2d-799d-acbb-79399e18bcd5" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_MY_019ebe77-3c2d-7ad2-a83b-60091d87b556" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_MY"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_AsiaPacificMember_019ebe77-3c2d-7f2b-9893-b12699300422" xlink:to="loc_country_MY_019ebe77-3c2d-7ad2-a83b-60091d87b556" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_CN_019ebe77-3c2d-74c9-a4fe-1f6c1ff0a126" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_CN"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_AsiaPacificMember_019ebe77-3c2d-7f2b-9893-b12699300422" xlink:to="loc_country_CN_019ebe77-3c2d-74c9-a4fe-1f6c1ff0a126" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_IL_019ebe77-3c2d-78e9-b46a-64083f9d92a8" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_IL"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_AsiaPacificMember_019ebe77-3c2d-7f2b-9893-b12699300422" xlink:to="loc_country_IL_019ebe77-3c2d-78e9-b46a-64083f9d92a8" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_JP_019ebe77-3c2d-7c42-8ae7-551c6af3dca6" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_JP"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_AsiaPacificMember_019ebe77-3c2d-7f2b-9893-b12699300422" xlink:to="loc_country_JP_019ebe77-3c2d-7c42-8ae7-551c6af3dca6" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_AsiaPacificOtherMember_019ebe77-3c2d-7981-a2c6-e8e5ccb168e1" xlink:href="fn-20260626.xsd#fn_AsiaPacificOtherMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_AsiaPacificMember_019ebe77-3c2d-7f2b-9893-b12699300422" xlink:to="loc_fn_AsiaPacificOtherMember_019ebe77-3c2d-7981-a2c6-e8e5ccb168e1" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_NorthAmericaMember_019ebe77-3c2d-7a1f-898c-8c22b97603a9" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_NorthAmericaMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_019ebe77-3c2d-7fed-a4be-0ae32fc814d6" xlink:to="loc_srt_NorthAmericaMember_019ebe77-3c2d-7a1f-898c-8c22b97603a9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_US_019ebe77-3c2d-7706-b875-c8fe3a9c907c" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_US"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NorthAmericaMember_019ebe77-3c2d-7a1f-898c-8c22b97603a9" xlink:to="loc_country_US_019ebe77-3c2d-7706-b875-c8fe3a9c907c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_MX_019f8e97-4afc-7ebf-9022-a9ad6000991a" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_MX"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NorthAmericaMember_019ebe77-3c2d-7a1f-898c-8c22b97603a9" xlink:to="loc_country_MX_019f8e97-4afc-7ebf-9022-a9ad6000991a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_NorthAmericaOtherMember_019ebe77-3c2d-7828-a841-870a2fe72e66" xlink:href="fn-20260626.xsd#fn_NorthAmericaOtherMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NorthAmericaMember_019ebe77-3c2d-7a1f-898c-8c22b97603a9" xlink:to="loc_fn_NorthAmericaOtherMember_019ebe77-3c2d-7828-a841-870a2fe72e66" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_KY_019ebe77-3c2d-7881-9ba2-2ed562e43397" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_KY"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NorthAmericaMember_019ebe77-3c2d-7a1f-898c-8c22b97603a9" xlink:to="loc_country_KY_019ebe77-3c2d-7881-9ba2-2ed562e43397" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EuropeMember_019ebe77-3c2d-78b4-aab8-8cb038e41ff7" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EuropeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_019ebe77-3c2d-7fed-a4be-0ae32fc814d6" xlink:to="loc_srt_EuropeMember_019ebe77-3c2d-78b4-aab8-8cb038e41ff7" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_DE_019ebe77-3c2d-7f9a-b6aa-452665b07c9c" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_DE"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EuropeMember_019ebe77-3c2d-78b4-aab8-8cb038e41ff7" xlink:to="loc_country_DE_019ebe77-3c2d-7f9a-b6aa-452665b07c9c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_GB_019ebe77-3c2d-711d-8caa-d5131b3be918" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_GB"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EuropeMember_019ebe77-3c2d-78b4-aab8-8cb038e41ff7" xlink:to="loc_country_GB_019ebe77-3c2d-711d-8caa-d5131b3be918" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_EuropeOtherMember_019ebe77-3c2d-74e8-a253-dd2ca418cb82" xlink:href="fn-20260626.xsd#fn_EuropeOtherMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EuropeMember_019ebe77-3c2d-78b4-aab8-8cb038e41ff7" xlink:to="loc_fn_EuropeOtherMember_019ebe77-3c2d-74e8-a253-dd2ca418cb82" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_019ebe77-3c2d-737c-b50c-213e808565ee" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskByBenchmarkAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_019ebe77-3c2d-7bd9-bd90-17e8a71d923a" xlink:to="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_019ebe77-3c2d-737c-b50c-213e808565ee" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019ebe77-3c2d-737c-b50c-213e808565ee_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_019ebe77-3c2d-737c-b50c-213e808565ee" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019ebe77-3c2d-737c-b50c-213e808565ee_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019ebe77-3c2d-7394-8413-a883fe847634" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_019ebe77-3c2d-737c-b50c-213e808565ee" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019ebe77-3c2d-7394-8413-a883fe847634" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerMember_019ebe77-3c2d-7248-8dad-3d26b9e707aa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueFromContractWithCustomerMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019ebe77-3c2d-7394-8413-a883fe847634" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerMember_019ebe77-3c2d-7248-8dad-3d26b9e707aa" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByTypeAxis_019ebe77-3c2d-7a40-b4c0-fb1045160f6d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskByTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_019ebe77-3c2d-7bd9-bd90-17e8a71d923a" xlink:to="loc_us-gaap_ConcentrationRiskByTypeAxis_019ebe77-3c2d-7a40-b4c0-fb1045160f6d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_019ebe77-3c2d-7a40-b4c0-fb1045160f6d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_019ebe77-3c2d-7a40-b4c0-fb1045160f6d" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_019ebe77-3c2d-7a40-b4c0-fb1045160f6d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_019ebe77-3c2d-77d3-b88e-fb62a93f20ed" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_019ebe77-3c2d-7a40-b4c0-fb1045160f6d" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_019ebe77-3c2d-77d3-b88e-fb62a93f20ed" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GeographicConcentrationRiskMember_019ebe77-3c2d-717e-ad42-b3afeba0d41e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GeographicConcentrationRiskMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskTypeDomain_019ebe77-3c2d-77d3-b88e-fb62a93f20ed" xlink:to="loc_us-gaap_GeographicConcentrationRiskMember_019ebe77-3c2d-717e-ad42-b3afeba0d41e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax_019ebe77-3c2d-7c70-855a-9e9211baefed" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ebe77-3c2d-79a3-927e-b2eb1b7ec3bc" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax_019ebe77-3c2d-7c70-855a-9e9211baefed" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskPercentage1_019ebe77-3c2d-7572-82b3-8d10d0540358" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskPercentage1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ebe77-3c2d-79a3-927e-b2eb1b7ec3bc" xlink:to="loc_us-gaap_ConcentrationRiskPercentage1_019ebe77-3c2d-7572-82b3-8d10d0540358" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/RevenuesfromcontractswithcustomersScheduleofRevenuesbyEndMarketDetails" xlink:type="simple" xlink:href="fn-20260626.xsd#RevenuesfromcontractswithcustomersScheduleofRevenuesbyEndMarketDetails"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/RevenuesfromcontractswithcustomersScheduleofRevenuesbyEndMarketDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueLineItems_019f92db-7a37-7a0c-a511-4a661c1cb21e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisaggregationOfRevenueLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueTable_019ebe77-3c2d-7d9c-83c3-ecc81632669f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisaggregationOfRevenueTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_019f92db-7a37-7a0c-a511-4a661c1cb21e" xlink:to="loc_us-gaap_DisaggregationOfRevenueTable_019ebe77-3c2d-7d9c-83c3-ecc81632669f" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_019f92db-7a37-7903-9981-3cfec0bfbea3" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_019ebe77-3c2d-7d9c-83c3-ecc81632669f" xlink:to="loc_srt_ProductOrServiceAxis_019f92db-7a37-7903-9981-3cfec0bfbea3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_019f92db-7a37-7903-9981-3cfec0bfbea3_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_019f92db-7a37-7903-9981-3cfec0bfbea3" xlink:to="loc_srt_ProductsAndServicesDomain_019f92db-7a37-7903-9981-3cfec0bfbea3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_019f92db-7a37-79e8-bc13-aad33479dae7" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_019f92db-7a37-7903-9981-3cfec0bfbea3" xlink:to="loc_srt_ProductsAndServicesDomain_019f92db-7a37-79e8-bc13-aad33479dae7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_DataCenterMember_019f92db-7a37-7edd-845c-7192012ec175" xlink:href="fn-20260626.xsd#fn_DataCenterMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_019f92db-7a37-79e8-bc13-aad33479dae7" xlink:to="loc_fn_DataCenterMember_019f92db-7a37-7edd-845c-7192012ec175" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_CommunicationsInfrastructureMember_019f92db-7a37-7c5b-8a00-d3ffa849dc73" xlink:href="fn-20260626.xsd#fn_CommunicationsInfrastructureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_019f92db-7a37-79e8-bc13-aad33479dae7" xlink:to="loc_fn_CommunicationsInfrastructureMember_019f92db-7a37-7c5b-8a00-d3ffa849dc73" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_AutomotiveIndustrialAndOthersMember_019f92db-7a37-7fc0-80c8-d2fc161ef768" xlink:href="fn-20260626.xsd#fn_AutomotiveIndustrialAndOthersMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_019f92db-7a37-79e8-bc13-aad33479dae7" xlink:to="loc_fn_AutomotiveIndustrialAndOthersMember_019f92db-7a37-7fc0-80c8-d2fc161ef768" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_019f92db-7a37-789d-bf91-dad9e4cc1f75" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskByBenchmarkAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_019ebe77-3c2d-7d9c-83c3-ecc81632669f" xlink:to="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_019f92db-7a37-789d-bf91-dad9e4cc1f75" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019f92db-7a37-789d-bf91-dad9e4cc1f75_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_019f92db-7a37-789d-bf91-dad9e4cc1f75" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019f92db-7a37-789d-bf91-dad9e4cc1f75_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019f92db-7a37-7818-8609-0e8b6300ceee" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_019f92db-7a37-789d-bf91-dad9e4cc1f75" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019f92db-7a37-7818-8609-0e8b6300ceee" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerMember_019f92db-7a37-7da8-a895-02ec27c06831" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueFromContractWithCustomerMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019f92db-7a37-7818-8609-0e8b6300ceee" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerMember_019f92db-7a37-7da8-a895-02ec27c06831" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByTypeAxis_019f92db-7a37-7255-be57-fc8e3bea02b3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskByTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_019ebe77-3c2d-7d9c-83c3-ecc81632669f" xlink:to="loc_us-gaap_ConcentrationRiskByTypeAxis_019f92db-7a37-7255-be57-fc8e3bea02b3" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_019f92db-7a37-7255-be57-fc8e3bea02b3_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_019f92db-7a37-7255-be57-fc8e3bea02b3" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_019f92db-7a37-7255-be57-fc8e3bea02b3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_019f92db-7a37-7da7-b6e6-7e221fabe59f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_019f92db-7a37-7255-be57-fc8e3bea02b3" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_019f92db-7a37-7da7-b6e6-7e221fabe59f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProductConcentrationRiskMember_019f92db-7a37-77f2-aef7-bf8ca080003f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProductConcentrationRiskMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskTypeDomain_019f92db-7a37-7da7-b6e6-7e221fabe59f" xlink:to="loc_us-gaap_ProductConcentrationRiskMember_019f92db-7a37-77f2-aef7-bf8ca080003f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax_019fd003-4df9-7fa6-bbb1-1ca625107e21" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_019f92db-7a37-7a0c-a511-4a661c1cb21e" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax_019fd003-4df9-7fa6-bbb1-1ca625107e21" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskPercentage1_019f92db-7a37-7766-9ebe-d9ea39c9b270" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskPercentage1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_019f92db-7a37-7a0c-a511-4a661c1cb21e" xlink:to="loc_us-gaap_ConcentrationRiskPercentage1_019f92db-7a37-7766-9ebe-d9ea39c9b270" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/IncometaxesAdditionalInformationDetails" xlink:type="simple" xlink:href="fn-20260626.xsd#IncometaxesAdditionalInformationDetails"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/IncometaxesAdditionalInformationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_fn_IncomeTaxesLineItems_019ebe77-3c2d-796f-b499-02e34b435314" xlink:href="fn-20260626.xsd#fn_IncomeTaxesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_IncomeTaxesTable_019ebe77-3c2d-780d-b079-95c944a833b4" xlink:href="fn-20260626.xsd#fn_IncomeTaxesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_fn_IncomeTaxesLineItems_019ebe77-3c2d-796f-b499-02e34b435314" xlink:to="loc_fn_IncomeTaxesTable_019ebe77-3c2d-780d-b079-95c944a833b4" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxAuthorityAxis_019ebe77-3c2d-790d-9a2e-a4da3fa3629d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxAuthorityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_fn_IncomeTaxesTable_019ebe77-3c2d-780d-b079-95c944a833b4" xlink:to="loc_us-gaap_IncomeTaxAuthorityAxis_019ebe77-3c2d-790d-9a2e-a4da3fa3629d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxAuthorityDomain_019ebe77-3c2d-790d-9a2e-a4da3fa3629d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxAuthorityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeTaxAuthorityAxis_019ebe77-3c2d-790d-9a2e-a4da3fa3629d" xlink:to="loc_us-gaap_IncomeTaxAuthorityDomain_019ebe77-3c2d-790d-9a2e-a4da3fa3629d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxAuthorityDomain_019ebe77-3c2d-7d9f-a742-21a442cf11e4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxAuthorityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeTaxAuthorityAxis_019ebe77-3c2d-790d-9a2e-a4da3fa3629d" xlink:to="loc_us-gaap_IncomeTaxAuthorityDomain_019ebe77-3c2d-7d9f-a742-21a442cf11e4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignCountryMember_019ebe77-3c2d-7730-a065-04007069273e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignCountryMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxAuthorityDomain_019ebe77-3c2d-7d9f-a742-21a442cf11e4" xlink:to="loc_us-gaap_ForeignCountryMember_019ebe77-3c2d-7730-a065-04007069273e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_TH_019ebe77-3c2d-7450-9a54-76e70dc44d8e" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_TH"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ForeignCountryMember_019ebe77-3c2d-7730-a065-04007069273e" xlink:to="loc_country_TH_019ebe77-3c2d-7450-9a54-76e70dc44d8e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_CN_019ebe77-3c2d-7199-a8d0-0f7f9d074c10" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_CN"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ForeignCountryMember_019ebe77-3c2d-7730-a065-04007069273e" xlink:to="loc_country_CN_019ebe77-3c2d-7199-a8d0-0f7f9d074c10" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_US_019ebe77-3c2d-72eb-9f2d-362124d11319" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_US"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ForeignCountryMember_019ebe77-3c2d-7730-a065-04007069273e" xlink:to="loc_country_US_019ebe77-3c2d-72eb-9f2d-362124d11319" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_GB_019ebe77-3c2d-7ffc-a071-5cc5eee8acea" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_GB"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ForeignCountryMember_019ebe77-3c2d-7730-a065-04007069273e" xlink:to="loc_country_GB_019ebe77-3c2d-7ffc-a071-5cc5eee8acea" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_IL_019ebe77-3c2d-7beb-85bb-273d3cdbaa55" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_IL"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ForeignCountryMember_019ebe77-3c2d-7730-a065-04007069273e" xlink:to="loc_country_IL_019ebe77-3c2d-7beb-85bb-273d3cdbaa55" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesAxis_019ebe77-3c2d-7ad4-b697-1fd2066f7470" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_fn_IncomeTaxesTable_019ebe77-3c2d-780d-b079-95c944a833b4" xlink:to="loc_srt_ConsolidatedEntitiesAxis_019ebe77-3c2d-7ad4-b697-1fd2066f7470" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_019ebe77-3c2d-7ad4-b697-1fd2066f7470_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidatedEntitiesAxis_019ebe77-3c2d-7ad4-b697-1fd2066f7470" xlink:to="loc_srt_ConsolidatedEntitiesDomain_019ebe77-3c2d-7ad4-b697-1fd2066f7470_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_019ebe77-3c2d-75e0-80a9-546121a2c39c" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidatedEntitiesAxis_019ebe77-3c2d-7ad4-b697-1fd2066f7470" xlink:to="loc_srt_ConsolidatedEntitiesDomain_019ebe77-3c2d-75e0-80a9-546121a2c39c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SubsidiariesMember_019ebe77-3c2d-75f8-ba8d-fd3443011b3f" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_SubsidiariesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_019ebe77-3c2d-75e0-80a9-546121a2c39c" xlink:to="loc_srt_SubsidiariesMember_019ebe77-3c2d-75f8-ba8d-fd3443011b3f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationTaxExemptIncome_019ebe77-3c2d-7c5c-b5f0-2618777e7501" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationTaxExemptIncome"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_IncomeTaxesLineItems_019ebe77-3c2d-796f-b499-02e34b435314" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateReconciliationTaxExemptIncome_019ebe77-3c2d-7c5c-b5f0-2618777e7501" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_PreferentialTaxTreatmentPeriod_019fd03c-4f8c-7ca7-a276-69313fab3c7f" xlink:href="fn-20260626.xsd#fn_PreferentialTaxTreatmentPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_IncomeTaxesLineItems_019ebe77-3c2d-796f-b499-02e34b435314" xlink:to="loc_fn_PreferentialTaxTreatmentPeriod_019fd03c-4f8c-7ca7-a276-69313fab3c7f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_IncomeTaxHolidayExemptionPeriod_019ebe77-3c2d-7082-b810-ce4f54b12880" xlink:href="fn-20260626.xsd#fn_IncomeTaxHolidayExemptionPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_IncomeTaxesLineItems_019ebe77-3c2d-796f-b499-02e34b435314" xlink:to="loc_fn_IncomeTaxHolidayExemptionPeriod_019ebe77-3c2d-7082-b810-ce4f54b12880" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_IncomeTaxHolidayReducedIncomeTaxRate_019ebe77-3c2d-766f-941c-5780ab0b9f2c" xlink:href="fn-20260626.xsd#fn_IncomeTaxHolidayReducedIncomeTaxRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_IncomeTaxesLineItems_019ebe77-3c2d-796f-b499-02e34b435314" xlink:to="loc_fn_IncomeTaxHolidayReducedIncomeTaxRate_019ebe77-3c2d-766f-941c-5780ab0b9f2c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_019ebe77-3c2d-77c3-af6b-c5bd69960936" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_IncomeTaxesLineItems_019ebe77-3c2d-796f-b499-02e34b435314" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_019ebe77-3c2d-77c3-af6b-c5bd69960936" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxAssetsValuationAllowance_019ebe77-3c2d-7224-b332-531379a95755" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredTaxAssetsValuationAllowance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_IncomeTaxesLineItems_019ebe77-3c2d-796f-b499-02e34b435314" xlink:to="loc_us-gaap_DeferredTaxAssetsValuationAllowance_019ebe77-3c2d-7224-b332-531379a95755" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount_019ebe77-3c2d-74fb-91f2-7e50332ce43b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_IncomeTaxesLineItems_019ebe77-3c2d-796f-b499-02e34b435314" xlink:to="loc_us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount_019ebe77-3c2d-74fb-91f2-7e50332ce43b" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UndistributedEarningsOfForeignSubsidiaries_019ebe77-3c2d-79da-89af-4912b009a563" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_UndistributedEarningsOfForeignSubsidiaries"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_IncomeTaxesLineItems_019ebe77-3c2d-796f-b499-02e34b435314" xlink:to="loc_us-gaap_UndistributedEarningsOfForeignSubsidiaries_019ebe77-3c2d-79da-89af-4912b009a563" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxLiabilityNotRecognizedAmountOfUnrecognizedDeferredTaxLiabilityUndistributedEarningsOfForeignSubsidiaries_019ebe77-3c2d-783d-a3bd-9759b8e01ec9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredTaxLiabilityNotRecognizedAmountOfUnrecognizedDeferredTaxLiabilityUndistributedEarningsOfForeignSubsidiaries"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_IncomeTaxesLineItems_019ebe77-3c2d-796f-b499-02e34b435314" xlink:to="loc_us-gaap_DeferredTaxLiabilityNotRecognizedAmountOfUnrecognizedDeferredTaxLiabilityUndistributedEarningsOfForeignSubsidiaries_019ebe77-3c2d-783d-a3bd-9759b8e01ec9" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxLiabilitiesUndistributedForeignEarnings_019ebe77-3c2d-7323-bef5-ddad8f3cb883" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredTaxLiabilitiesUndistributedForeignEarnings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_IncomeTaxesLineItems_019ebe77-3c2d-796f-b499-02e34b435314" xlink:to="loc_us-gaap_DeferredTaxLiabilitiesUndistributedForeignEarnings_019ebe77-3c2d-7323-bef5-ddad8f3cb883" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExaminationPenaltiesAndInterestAccrued_019ebe77-3c2d-7f3c-bf84-55c6aac996e3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxExaminationPenaltiesAndInterestAccrued"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_IncomeTaxesLineItems_019ebe77-3c2d-796f-b499-02e34b435314" xlink:to="loc_us-gaap_IncomeTaxExaminationPenaltiesAndInterestAccrued_019ebe77-3c2d-7f3c-bf84-55c6aac996e3" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExaminationPenaltiesAndInterestExpense_019ebe77-3c2d-7c60-be83-943789cc5f8a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxExaminationPenaltiesAndInterestExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_IncomeTaxesLineItems_019ebe77-3c2d-796f-b499-02e34b435314" xlink:to="loc_us-gaap_IncomeTaxExaminationPenaltiesAndInterestExpense_019ebe77-3c2d-7c60-be83-943789cc5f8a" xlink:type="arc" order="11"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/IncometaxesScheduleofIncomeBeforeIncomeTaxDetails" xlink:type="simple" xlink:href="fn-20260626.xsd#IncometaxesScheduleofIncomeBeforeIncomeTaxDetails"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/IncometaxesScheduleofIncomeBeforeIncomeTaxDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_fn_IncomeTaxesLineItems_019f8f2d-db94-75ab-8ce0-67a7fd8b9956" xlink:href="fn-20260626.xsd#fn_IncomeTaxesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationTable_019f8f24-8041-7030-adf2-916270eb1537" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_fn_IncomeTaxesLineItems_019f8f2d-db94-75ab-8ce0-67a7fd8b9956" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateReconciliationTable_019f8f24-8041-7030-adf2-916270eb1537" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxAuthorityAxis_019f8f24-c019-7962-9083-9ec6301a0875" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxAuthorityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateReconciliationTable_019f8f24-8041-7030-adf2-916270eb1537" xlink:to="loc_us-gaap_IncomeTaxAuthorityAxis_019f8f24-c019-7962-9083-9ec6301a0875" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxAuthorityDomain_019f8f24-c019-7962-9083-9ec6301a0875_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxAuthorityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeTaxAuthorityAxis_019f8f24-c019-7962-9083-9ec6301a0875" xlink:to="loc_us-gaap_IncomeTaxAuthorityDomain_019f8f24-c019-7962-9083-9ec6301a0875_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxAuthorityDomain_019f8f24-f3c1-7e89-9b7c-0965920bd131" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxAuthorityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeTaxAuthorityAxis_019f8f24-c019-7962-9083-9ec6301a0875" xlink:to="loc_us-gaap_IncomeTaxAuthorityDomain_019f8f24-f3c1-7e89-9b7c-0965920bd131" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignCountryMember_019f8f3a-c620-7d09-a8f2-6a31798ea6ab" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignCountryMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxAuthorityDomain_019f8f24-f3c1-7e89-9b7c-0965920bd131" xlink:to="loc_us-gaap_ForeignCountryMember_019f8f3a-c620-7d09-a8f2-6a31798ea6ab" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_TH_019f8f2c-64e9-7764-a1b9-dfc569e50701" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_TH"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ForeignCountryMember_019f8f3a-c620-7d09-a8f2-6a31798ea6ab" xlink:to="loc_country_TH_019f8f2c-64e9-7764-a1b9-dfc569e50701" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_InternationalMember_019f8f2c-efe3-7621-9d41-1c307569b140" xlink:href="fn-20260626.xsd#fn_InternationalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ForeignCountryMember_019f8f3a-c620-7d09-a8f2-6a31798ea6ab" xlink:to="loc_fn_InternationalMember_019f8f2c-efe3-7621-9d41-1c307569b140" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign_019f8f21-ccf0-7e82-9dd4-47de1fb15385" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_IncomeTaxesLineItems_019f8f2d-db94-75ab-8ce0-67a7fd8b9956" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign_019f8f21-ccf0-7e82-9dd4-47de1fb15385" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019f8f2a-0895-7f42-8c8a-335034ebed15" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_IncomeTaxesLineItems_019f8f2d-db94-75ab-8ce0-67a7fd8b9956" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019f8f2a-0895-7f42-8c8a-335034ebed15" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/IncometaxesScheduleofIncomeTaxPaidDetails" xlink:type="simple" xlink:href="fn-20260626.xsd#IncometaxesScheduleofIncomeTaxPaidDetails"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/IncometaxesScheduleofIncomeTaxPaidDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxPaidByIndividualJurisdictionLineItems_019f8f3d-2d23-77ab-bf7e-ff0397fe8f40" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxPaidByIndividualJurisdictionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxPaidByIndividualJurisdictionTable_019f8f35-1140-79f9-8db5-9af253fae491" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxPaidByIndividualJurisdictionTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_IncomeTaxPaidByIndividualJurisdictionLineItems_019f8f3d-2d23-77ab-bf7e-ff0397fe8f40" xlink:to="loc_us-gaap_IncomeTaxPaidByIndividualJurisdictionTable_019f8f35-1140-79f9-8db5-9af253fae491" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxAuthorityAxis_019f8f35-5557-723f-bc92-1b646d5d293e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxAuthorityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_IncomeTaxPaidByIndividualJurisdictionTable_019f8f35-1140-79f9-8db5-9af253fae491" xlink:to="loc_us-gaap_IncomeTaxAuthorityAxis_019f8f35-5557-723f-bc92-1b646d5d293e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxAuthorityDomain_019f8f35-5557-723f-bc92-1b646d5d293e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxAuthorityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeTaxAuthorityAxis_019f8f35-5557-723f-bc92-1b646d5d293e" xlink:to="loc_us-gaap_IncomeTaxAuthorityDomain_019f8f35-5557-723f-bc92-1b646d5d293e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxAuthorityDomain_019f8f35-9615-732c-b5b2-c968f57c3dca" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxAuthorityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeTaxAuthorityAxis_019f8f35-5557-723f-bc92-1b646d5d293e" xlink:to="loc_us-gaap_IncomeTaxAuthorityDomain_019f8f35-9615-732c-b5b2-c968f57c3dca" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignCountryMember_019f8f3b-8e62-7908-aa09-a40c00655c3f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignCountryMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxAuthorityDomain_019f8f35-9615-732c-b5b2-c968f57c3dca" xlink:to="loc_us-gaap_ForeignCountryMember_019f8f3b-8e62-7908-aa09-a40c00655c3f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_TH_019f8f3b-d253-7ba8-b421-07535ba50f5a" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_TH"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ForeignCountryMember_019f8f3b-8e62-7908-aa09-a40c00655c3f" xlink:to="loc_country_TH_019f8f3b-d253-7ba8-b421-07535ba50f5a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_US_019f8f3c-464c-7da5-af4b-df1b415d82dd" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_US"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ForeignCountryMember_019f8f3b-8e62-7908-aa09-a40c00655c3f" xlink:to="loc_country_US_019f8f3c-464c-7da5-af4b-df1b415d82dd" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_CN_019f8f3c-6a73-7959-9c91-15b61353f66c" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_CN"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ForeignCountryMember_019f8f3b-8e62-7908-aa09-a40c00655c3f" xlink:to="loc_country_CN_019f8f3c-6a73-7959-9c91-15b61353f66c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignTaxJurisdictionOtherMember_019f8f3c-e7dc-70c9-b562-4a4d39df6e72" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignTaxJurisdictionOtherMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ForeignCountryMember_019f8f3b-8e62-7908-aa09-a40c00655c3f" xlink:to="loc_us-gaap_ForeignTaxJurisdictionOtherMember_019f8f3c-e7dc-70c9-b562-4a4d39df6e72" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxPaidForeignAfterRefundReceived_019f8f3e-eb43-78c5-a2d6-d6a7946a6db5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxPaidForeignAfterRefundReceived"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxPaidByIndividualJurisdictionLineItems_019f8f3d-2d23-77ab-bf7e-ff0397fe8f40" xlink:to="loc_us-gaap_IncomeTaxPaidForeignAfterRefundReceived_019f8f3e-eb43-78c5-a2d6-d6a7946a6db5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxesPaidNet_019f8f3f-3443-7b3f-b1f1-3220fc12f78d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxesPaidNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxPaidByIndividualJurisdictionLineItems_019f8f3d-2d23-77ab-bf7e-ff0397fe8f40" xlink:to="loc_us-gaap_IncomeTaxesPaidNet_019f8f3f-3443-7b3f-b1f1-3220fc12f78d" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/IncomeTaxesScheduleofReconciliationofStatutorytaxrateoftheCountryoftheCompanyDetails" xlink:type="simple" xlink:href="fn-20260626.xsd#IncomeTaxesScheduleofReconciliationofStatutorytaxrateoftheCountryoftheCompanyDetails"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/IncomeTaxesScheduleofReconciliationofStatutorytaxrateoftheCountryoftheCompanyDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationLineItems_019f8f66-5a9c-7a1d-84a6-0b22cd4dcb27" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationTable_019f8f63-53fc-7f91-8a0c-5f1ead465677" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateReconciliationLineItems_019f8f66-5a9c-7a1d-84a6-0b22cd4dcb27" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateReconciliationTable_019f8f63-53fc-7f91-8a0c-5f1ead465677" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxAuthorityAxis_019f8f63-8e06-7315-a2f9-9d6ff7452d1f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxAuthorityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateReconciliationTable_019f8f63-53fc-7f91-8a0c-5f1ead465677" xlink:to="loc_us-gaap_IncomeTaxAuthorityAxis_019f8f63-8e06-7315-a2f9-9d6ff7452d1f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxAuthorityDomain_019f8f63-8e06-7315-a2f9-9d6ff7452d1f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxAuthorityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeTaxAuthorityAxis_019f8f63-8e06-7315-a2f9-9d6ff7452d1f" xlink:to="loc_us-gaap_IncomeTaxAuthorityDomain_019f8f63-8e06-7315-a2f9-9d6ff7452d1f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxAuthorityDomain_019f8f63-baae-73af-b7ac-f27cd2f0bbc0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxAuthorityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeTaxAuthorityAxis_019f8f63-8e06-7315-a2f9-9d6ff7452d1f" xlink:to="loc_us-gaap_IncomeTaxAuthorityDomain_019f8f63-baae-73af-b7ac-f27cd2f0bbc0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignCountryMember_019f8f64-1b7e-7982-b09d-cd8c64faba5f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignCountryMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxAuthorityDomain_019f8f63-baae-73af-b7ac-f27cd2f0bbc0" xlink:to="loc_us-gaap_ForeignCountryMember_019f8f64-1b7e-7982-b09d-cd8c64faba5f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_TH_019f8f69-3f83-7f62-970e-0d3ae183d8c1" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_TH"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ForeignCountryMember_019f8f64-1b7e-7982-b09d-cd8c64faba5f" xlink:to="loc_country_TH_019f8f69-3f83-7f62-970e-0d3ae183d8c1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_US_019f8f65-0d93-72a9-93c1-f5146ae17382" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_US"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ForeignCountryMember_019f8f64-1b7e-7982-b09d-cd8c64faba5f" xlink:to="loc_country_US_019f8f65-0d93-72a9-93c1-f5146ae17382" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_KY_019f8f65-3c22-7d6d-afe9-5d743a053f72" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_KY"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ForeignCountryMember_019f8f64-1b7e-7982-b09d-cd8c64faba5f" xlink:to="loc_country_KY_019f8f65-3c22-7d6d-afe9-5d743a053f72" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignTaxJurisdictionOtherMember_019f8f65-d037-7d16-b71f-c2f5dbd9e6f3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignTaxJurisdictionOtherMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ForeignCountryMember_019f8f64-1b7e-7982-b09d-cd8c64faba5f" xlink:to="loc_us-gaap_ForeignTaxJurisdictionOtherMember_019f8f65-d037-7d16-b71f-c2f5dbd9e6f3" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefitContinuingOperationsIncomeTaxReconciliationAbstract_019f8f6b-022b-72c5-ab2d-84df57445755" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxExpenseBenefitContinuingOperationsIncomeTaxReconciliationAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateReconciliationLineItems_019f8f66-5a9c-7a1d-84a6-0b22cd4dcb27" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefitContinuingOperationsIncomeTaxReconciliationAbstract_019f8f6b-022b-72c5-ab2d-84df57445755" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate_019f8f67-3b89-7793-ae24-b112f90a2e9c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefitContinuingOperationsIncomeTaxReconciliationAbstract_019f8f6b-022b-72c5-ab2d-84df57445755" xlink:to="loc_us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate_019f8f67-3b89-7793-ae24-b112f90a2e9c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxReconciliationForeignIncomeTaxRateDifferential_019f8f6e-6089-759f-9f78-104b0076e2c5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxReconciliationForeignIncomeTaxRateDifferential"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefitContinuingOperationsIncomeTaxReconciliationAbstract_019f8f6b-022b-72c5-ab2d-84df57445755" xlink:to="loc_us-gaap_IncomeTaxReconciliationForeignIncomeTaxRateDifferential_019f8f6e-6089-759f-9f78-104b0076e2c5" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxReconciliationNondeductibleExpense_019f8f93-0cd1-7b63-85ca-c2ead8a7f15f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxReconciliationNondeductibleExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefitContinuingOperationsIncomeTaxReconciliationAbstract_019f8f6b-022b-72c5-ab2d-84df57445755" xlink:to="loc_us-gaap_IncomeTaxReconciliationNondeductibleExpense_019f8f93-0cd1-7b63-85ca-c2ead8a7f15f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxReconciliationOtherAdjustments_019fc715-a60d-7eb9-a515-c4f522986a69" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxReconciliationOtherAdjustments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefitContinuingOperationsIncomeTaxReconciliationAbstract_019f8f6b-022b-72c5-ab2d-84df57445755" xlink:to="loc_us-gaap_IncomeTaxReconciliationOtherAdjustments_019fc715-a60d-7eb9-a515-c4f522986a69" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_EffectiveIncomeTaxRateReconciliationPillarTwoTopUpTaxAmount_019fea7e-8e3a-7b98-ac9c-bd60b753a525" xlink:href="fn-20260626.xsd#fn_EffectiveIncomeTaxRateReconciliationPillarTwoTopUpTaxAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefitContinuingOperationsIncomeTaxReconciliationAbstract_019f8f6b-022b-72c5-ab2d-84df57445755" xlink:to="loc_fn_EffectiveIncomeTaxRateReconciliationPillarTwoTopUpTaxAmount_019fea7e-8e3a-7b98-ac9c-bd60b753a525" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxReconciliationTaxContingencies_019f8f99-6863-7a14-9dd0-65e1a2a73c64" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxReconciliationTaxContingencies"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefitContinuingOperationsIncomeTaxReconciliationAbstract_019f8f6b-022b-72c5-ab2d-84df57445755" xlink:to="loc_us-gaap_IncomeTaxReconciliationTaxContingencies_019f8f99-6863-7a14-9dd0-65e1a2a73c64" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_019f8f98-61fe-7b6e-afa4-d7f9c37f9149" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxExpenseBenefit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefitContinuingOperationsIncomeTaxReconciliationAbstract_019f8f6b-022b-72c5-ab2d-84df57445755" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_019f8f98-61fe-7b6e-afa4-d7f9c37f9149" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract_019f8f6b-c7b3-7091-8aec-b92048b94d94" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateReconciliationLineItems_019f8f66-5a9c-7a1d-84a6-0b22cd4dcb27" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract_019f8f6b-c7b3-7091-8aec-b92048b94d94" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_019f8f6c-43a5-7f90-950a-6010ea014664" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract_019f8f6b-c7b3-7091-8aec-b92048b94d94" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_019f8f6c-43a5-7f90-950a-6010ea014664" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential_019f8f70-d136-720e-971d-0cde886cea35" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract_019f8f6b-c7b3-7091-8aec-b92048b94d94" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential_019f8f70-d136-720e-971d-0cde886cea35" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpense_019f8fab-04a1-75cb-9421-6057f62f795e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract_019f8f6b-c7b3-7091-8aec-b92048b94d94" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpense_019f8fab-04a1-75cb-9421-6057f62f795e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationOtherAdjustments_019f8fa4-3e4d-7698-9db7-731fdf387556" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationOtherAdjustments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract_019f8f6b-c7b3-7091-8aec-b92048b94d94" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateReconciliationOtherAdjustments_019f8fa4-3e4d-7698-9db7-731fdf387556" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_EffectiveIncomeTaxRateReconciliationPillarTwoTopUpTaxPercent_019fea7e-d681-765d-872e-73d41311b8c1" xlink:href="fn-20260626.xsd#fn_EffectiveIncomeTaxRateReconciliationPillarTwoTopUpTaxPercent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract_019f8f6b-c7b3-7091-8aec-b92048b94d94" xlink:to="loc_fn_EffectiveIncomeTaxRateReconciliationPillarTwoTopUpTaxPercent_019fea7e-d681-765d-872e-73d41311b8c1" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationTaxContingencies_019f8fa3-2d38-7fc5-a770-7097c44e1e9a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationTaxContingencies"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract_019f8f6b-c7b3-7091-8aec-b92048b94d94" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateReconciliationTaxContingencies_019f8fa3-2d38-7fc5-a770-7097c44e1e9a" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_019f8fa2-7d2f-76ea-8f99-c7ee828a98ad" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EffectiveIncomeTaxRateContinuingOperations"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperationsTaxRateReconciliationAbstract_019f8f6b-c7b3-7091-8aec-b92048b94d94" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_019f8fa2-7d2f-76ea-8f99-c7ee828a98ad" xlink:type="arc" order="7"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/IncometaxesScheduleofEffectiveTaxRateDetails" xlink:type="simple" xlink:href="fn-20260626.xsd#IncometaxesScheduleofEffectiveTaxRateDetails"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/IncometaxesScheduleofEffectiveTaxRateDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_fn_IncomeTaxesLineItems_019ebe77-3c2d-7860-b0a6-99e9e6f1a791" xlink:href="fn-20260626.xsd#fn_IncomeTaxesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_IncomeTaxesTable_019ebe77-3c2d-7e34-a254-156b198694c8" xlink:href="fn-20260626.xsd#fn_IncomeTaxesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_fn_IncomeTaxesLineItems_019ebe77-3c2d-7860-b0a6-99e9e6f1a791" xlink:to="loc_fn_IncomeTaxesTable_019ebe77-3c2d-7e34-a254-156b198694c8" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxAuthorityAxis_019ebe77-3c2d-7563-ac47-2c73f2c12b3c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxAuthorityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_fn_IncomeTaxesTable_019ebe77-3c2d-7e34-a254-156b198694c8" xlink:to="loc_us-gaap_IncomeTaxAuthorityAxis_019ebe77-3c2d-7563-ac47-2c73f2c12b3c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxAuthorityDomain_019ebe77-3c2d-7563-ac47-2c73f2c12b3c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxAuthorityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeTaxAuthorityAxis_019ebe77-3c2d-7563-ac47-2c73f2c12b3c" xlink:to="loc_us-gaap_IncomeTaxAuthorityDomain_019ebe77-3c2d-7563-ac47-2c73f2c12b3c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxAuthorityDomain_019ebe77-3c2d-7414-9f2b-ad88e9ebedd4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxAuthorityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeTaxAuthorityAxis_019ebe77-3c2d-7563-ac47-2c73f2c12b3c" xlink:to="loc_us-gaap_IncomeTaxAuthorityDomain_019ebe77-3c2d-7414-9f2b-ad88e9ebedd4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DomesticCountryMember_019ebe77-3c2d-74da-aa14-6792bc452f2c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DomesticCountryMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxAuthorityDomain_019ebe77-3c2d-7414-9f2b-ad88e9ebedd4" xlink:to="loc_us-gaap_DomesticCountryMember_019ebe77-3c2d-74da-aa14-6792bc452f2c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019ebe77-3c2d-772a-81b7-051e7594c6be" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_IncomeTaxesLineItems_019ebe77-3c2d-7860-b0a6-99e9e6f1a791" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019ebe77-3c2d-772a-81b7-051e7594c6be" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_019fcff4-9489-718d-977e-0536a8090d81" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_IncomeTaxesLineItems_019ebe77-3c2d-7860-b0a6-99e9e6f1a791" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_019fcff4-9489-718d-977e-0536a8090d81" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate_019ebe77-3c2d-72d6-b6ca-e4d88c9fdeac" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_IncomeTaxesLineItems_019ebe77-3c2d-7860-b0a6-99e9e6f1a791" xlink:to="loc_us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate_019ebe77-3c2d-72d6-b6ca-e4d88c9fdeac" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxReconciliationForeignIncomeTaxRateDifferential_019ebe77-3c2d-7a50-9f74-3f9cab58b5bd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxReconciliationForeignIncomeTaxRateDifferential"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_IncomeTaxesLineItems_019ebe77-3c2d-7860-b0a6-99e9e6f1a791" xlink:to="loc_us-gaap_IncomeTaxReconciliationForeignIncomeTaxRateDifferential_019ebe77-3c2d-7a50-9f74-3f9cab58b5bd" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxReconciliationTaxExemptIncome_019ebe77-3c2d-7edd-aa8d-314ffb512e63" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxReconciliationTaxExemptIncome"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_IncomeTaxesLineItems_019ebe77-3c2d-7860-b0a6-99e9e6f1a791" xlink:to="loc_us-gaap_IncomeTaxReconciliationTaxExemptIncome_019ebe77-3c2d-7edd-aa8d-314ffb512e63" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_IncomeTaxReconciliationInUndistributedEarnings_019ebe77-3c2d-73e8-9d8d-54f979653917" xlink:href="fn-20260626.xsd#fn_IncomeTaxReconciliationInUndistributedEarnings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_IncomeTaxesLineItems_019ebe77-3c2d-7860-b0a6-99e9e6f1a791" xlink:to="loc_fn_IncomeTaxReconciliationInUndistributedEarnings_019ebe77-3c2d-73e8-9d8d-54f979653917" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxReconciliationNondeductibleExpense_019ebe77-3c2d-779c-8c05-30e52bc04685" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxReconciliationNondeductibleExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_IncomeTaxesLineItems_019ebe77-3c2d-7860-b0a6-99e9e6f1a791" xlink:to="loc_us-gaap_IncomeTaxReconciliationNondeductibleExpense_019ebe77-3c2d-779c-8c05-30e52bc04685" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_IncomeTaxReconciliationEffectOfForeignOperations_019ebe77-3c2d-735a-9d03-41a773ad29b6" xlink:href="fn-20260626.xsd#fn_IncomeTaxReconciliationEffectOfForeignOperations"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_IncomeTaxesLineItems_019ebe77-3c2d-7860-b0a6-99e9e6f1a791" xlink:to="loc_fn_IncomeTaxReconciliationEffectOfForeignOperations_019ebe77-3c2d-735a-9d03-41a773ad29b6" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_IncomeTaxReconciliationTaxCreditsResearchAndDevelopment_019ebe77-3c2d-773e-9f39-9a0adf7aff74" xlink:href="fn-20260626.xsd#fn_IncomeTaxReconciliationTaxCreditsResearchAndDevelopment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_IncomeTaxesLineItems_019ebe77-3c2d-7860-b0a6-99e9e6f1a791" xlink:to="loc_fn_IncomeTaxReconciliationTaxCreditsResearchAndDevelopment_019ebe77-3c2d-773e-9f39-9a0adf7aff74" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_IncomeTaxReconciliationUncertainTaxPositions_019ebe77-3c2d-78f4-acec-c3dcd6352367" xlink:href="fn-20260626.xsd#fn_IncomeTaxReconciliationUncertainTaxPositions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_IncomeTaxesLineItems_019ebe77-3c2d-7860-b0a6-99e9e6f1a791" xlink:to="loc_fn_IncomeTaxReconciliationUncertainTaxPositions_019ebe77-3c2d-78f4-acec-c3dcd6352367" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_IncomeTaxReconciliationUtilizationOfOperatingLossCarryForwards_019ebe77-3c2d-76f7-a69a-ae1df4ffeab0" xlink:href="fn-20260626.xsd#fn_IncomeTaxReconciliationUtilizationOfOperatingLossCarryForwards"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_IncomeTaxesLineItems_019ebe77-3c2d-7860-b0a6-99e9e6f1a791" xlink:to="loc_fn_IncomeTaxReconciliationUtilizationOfOperatingLossCarryForwards_019ebe77-3c2d-76f7-a69a-ae1df4ffeab0" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_IncomeTaxReconciliationReversalOfValuationAllowance_019ebe77-3c2d-75cc-8883-38c351ab0d4b" xlink:href="fn-20260626.xsd#fn_IncomeTaxReconciliationReversalOfValuationAllowance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_IncomeTaxesLineItems_019ebe77-3c2d-7860-b0a6-99e9e6f1a791" xlink:to="loc_fn_IncomeTaxReconciliationReversalOfValuationAllowance_019ebe77-3c2d-75cc-8883-38c351ab0d4b" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxReconciliationOtherReconcilingItems_019ebe77-3c2d-7e6b-8091-518c1778e275" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxReconciliationOtherReconcilingItems"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_IncomeTaxesLineItems_019ebe77-3c2d-7860-b0a6-99e9e6f1a791" xlink:to="loc_us-gaap_IncomeTaxReconciliationOtherReconcilingItems_019ebe77-3c2d-7e6b-8091-518c1778e275" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_019ebe77-3c2d-76aa-a1c3-2af1920ebdeb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxExpenseBenefit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_IncomeTaxesLineItems_019ebe77-3c2d-7860-b0a6-99e9e6f1a791" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_019ebe77-3c2d-76aa-a1c3-2af1920ebdeb" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_IncomeTaxHolidayIncomeTaxBenefitsExpensePerShare_019ebe77-3c2d-7d67-a22e-537cc851dd74" xlink:href="fn-20260626.xsd#fn_IncomeTaxHolidayIncomeTaxBenefitsExpensePerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_IncomeTaxesLineItems_019ebe77-3c2d-7860-b0a6-99e9e6f1a791" xlink:to="loc_fn_IncomeTaxHolidayIncomeTaxBenefitsExpensePerShare_019ebe77-3c2d-7d67-a22e-537cc851dd74" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TaxJurisdictionOfDomicileExtensibleEnumeration_019fca7a-8ae2-7ccf-b279-ac7030aab0e4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TaxJurisdictionOfDomicileExtensibleEnumeration"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_IncomeTaxesLineItems_019ebe77-3c2d-7860-b0a6-99e9e6f1a791" xlink:to="loc_us-gaap_TaxJurisdictionOfDomicileExtensibleEnumeration_019fca7a-8ae2-7ccf-b279-ac7030aab0e4" xlink:type="arc" order="15"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/CashcashequivalentsandshortterminvestmentsScheduleofCashCashEquivalentsandShortTermInvestmentsDetails" xlink:type="simple" xlink:href="fn-20260626.xsd#CashcashequivalentsandshortterminvestmentsScheduleofCashCashEquivalentsandShortTermInvestmentsDetails"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/CashcashequivalentsandshortterminvestmentsScheduleofCashCashEquivalentsandShortTermInvestmentsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_fn_CashCashEquivalentsAndMarketableSecuritiesLineItems_019ebe77-3c2d-706e-8b33-126eb967d671" xlink:href="fn-20260626.xsd#fn_CashCashEquivalentsAndMarketableSecuritiesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_CashCashEquivalentsAndMarketableSecuritiesTable_019ebe77-3c2d-7004-9a42-e623c85f4d8a" xlink:href="fn-20260626.xsd#fn_CashCashEquivalentsAndMarketableSecuritiesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_fn_CashCashEquivalentsAndMarketableSecuritiesLineItems_019ebe77-3c2d-706e-8b33-126eb967d671" xlink:to="loc_fn_CashCashEquivalentsAndMarketableSecuritiesTable_019ebe77-3c2d-7004-9a42-e623c85f4d8a" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_019ebe77-3c2d-7c5e-9e40-41e00826dd19" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_fn_CashCashEquivalentsAndMarketableSecuritiesTable_019ebe77-3c2d-7004-9a42-e623c85f4d8a" xlink:to="loc_us-gaap_FinancialInstrumentAxis_019ebe77-3c2d-7c5e-9e40-41e00826dd19" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019ebe77-3c2d-7c5e-9e40-41e00826dd19_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019ebe77-3c2d-7c5e-9e40-41e00826dd19" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019ebe77-3c2d-7c5e-9e40-41e00826dd19_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019ebe77-3c2d-7adc-a306-7ff4f9b010f4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019ebe77-3c2d-7c5e-9e40-41e00826dd19" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019ebe77-3c2d-7adc-a306-7ff4f9b010f4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashMember_019ebe77-3c2d-7ad1-aca5-74b1aa0f011d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019ebe77-3c2d-7adc-a306-7ff4f9b010f4" xlink:to="loc_us-gaap_CashMember_019ebe77-3c2d-7ad1-aca5-74b1aa0f011d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashEquivalentsMember_019ebe77-3c2d-7b11-9f6b-f3a51b0e619f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashEquivalentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019ebe77-3c2d-7adc-a306-7ff4f9b010f4" xlink:to="loc_us-gaap_CashEquivalentsMember_019ebe77-3c2d-7b11-9f6b-f3a51b0e619f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestBearingDepositsMember_019ebe77-3c2d-7918-98e6-14034e63e6c6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestBearingDepositsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019ebe77-3c2d-7adc-a306-7ff4f9b010f4" xlink:to="loc_us-gaap_InterestBearingDepositsMember_019ebe77-3c2d-7918-98e6-14034e63e6c6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateDebtSecuritiesMember_019ebe77-3c2d-79bb-9472-f4a81a2290cb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CorporateDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019ebe77-3c2d-7adc-a306-7ff4f9b010f4" xlink:to="loc_us-gaap_CorporateDebtSecuritiesMember_019ebe77-3c2d-79bb-9472-f4a81a2290cb" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_USTreasurySecuritiesAndUSGovernmentAndAgencySecuritiesMember_019ebe77-3c2d-7424-b923-78ab6f6c24ed" xlink:href="fn-20260626.xsd#fn_USTreasurySecuritiesAndUSGovernmentAndAgencySecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019ebe77-3c2d-7adc-a306-7ff4f9b010f4" xlink:to="loc_fn_USTreasurySecuritiesAndUSGovernmentAndAgencySecuritiesMember_019ebe77-3c2d-7424-b923-78ab6f6c24ed" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_CashAndCashEquivalentsAtCost_019ebe77-3c2d-7102-9258-9ea6608473af" xlink:href="fn-20260626.xsd#fn_CashAndCashEquivalentsAtCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_CashCashEquivalentsAndMarketableSecuritiesLineItems_019ebe77-3c2d-706e-8b33-126eb967d671" xlink:to="loc_fn_CashAndCashEquivalentsAtCost_019ebe77-3c2d-7102-9258-9ea6608473af" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_019ebe77-3c2d-79da-b1c5-c999ddd89fce" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_CashCashEquivalentsAndMarketableSecuritiesLineItems_019ebe77-3c2d-706e-8b33-126eb967d671" xlink:to="loc_us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_019ebe77-3c2d-79da-b1c5-c999ddd89fce" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_CashAndCashEquivalentsAndMarketableSecuritiesCarryingCost_019ebe77-3c2d-7f56-8364-40e2fdeaaeb4" xlink:href="fn-20260626.xsd#fn_CashAndCashEquivalentsAndMarketableSecuritiesCarryingCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_CashCashEquivalentsAndMarketableSecuritiesLineItems_019ebe77-3c2d-706e-8b33-126eb967d671" xlink:to="loc_fn_CashAndCashEquivalentsAndMarketableSecuritiesCarryingCost_019ebe77-3c2d-7f56-8364-40e2fdeaaeb4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleAccumulatedGrossUnrealizedGainLossBeforeTax_019ebe77-3c2d-7587-855c-7ff1f4560bf8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleAccumulatedGrossUnrealizedGainLossBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_CashCashEquivalentsAndMarketableSecuritiesLineItems_019ebe77-3c2d-706e-8b33-126eb967d671" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleAccumulatedGrossUnrealizedGainLossBeforeTax_019ebe77-3c2d-7587-855c-7ff1f4560bf8" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_019ebe77-3c2d-7c73-a979-22a9584e9716" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_CashCashEquivalentsAndMarketableSecuritiesLineItems_019ebe77-3c2d-706e-8b33-126eb967d671" xlink:to="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_019ebe77-3c2d-7c73-a979-22a9584e9716" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShortTermInvestments_019ebe77-3c2d-79b8-bd76-0e9cc119efb6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShortTermInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_CashCashEquivalentsAndMarketableSecuritiesLineItems_019ebe77-3c2d-706e-8b33-126eb967d671" xlink:to="loc_us-gaap_ShortTermInvestments_019ebe77-3c2d-79b8-bd76-0e9cc119efb6" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherInvestments_019ebe77-3c2d-7f13-bcad-e0423469cf92" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_CashCashEquivalentsAndMarketableSecuritiesLineItems_019ebe77-3c2d-706e-8b33-126eb967d671" xlink:to="loc_us-gaap_OtherInvestments_019ebe77-3c2d-7f13-bcad-e0423469cf92" xlink:type="arc" order="6"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/CashcashequivalentsandshortterminvestmentsAdditionalInformationDetails" xlink:type="simple" xlink:href="fn-20260626.xsd#CashcashequivalentsandshortterminvestmentsAdditionalInformationDetails"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/CashcashequivalentsandshortterminvestmentsAdditionalInformationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_fn_CashCashEquivalentsAndMarketableSecuritiesLineItems_019ebe77-3c2d-7b71-afba-76b7d6b757db" xlink:href="fn-20260626.xsd#fn_CashCashEquivalentsAndMarketableSecuritiesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_CashCashEquivalentsAndMarketableSecuritiesTable_019ebe77-3c2d-7249-8b79-132119022f0f" xlink:href="fn-20260626.xsd#fn_CashCashEquivalentsAndMarketableSecuritiesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_fn_CashCashEquivalentsAndMarketableSecuritiesLineItems_019ebe77-3c2d-7b71-afba-76b7d6b757db" xlink:to="loc_fn_CashCashEquivalentsAndMarketableSecuritiesTable_019ebe77-3c2d-7249-8b79-132119022f0f" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsAxis_019ebe77-3c2d-7c09-bd54-526a7f996e5b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashAndCashEquivalentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_fn_CashCashEquivalentsAndMarketableSecuritiesTable_019ebe77-3c2d-7249-8b79-132119022f0f" xlink:to="loc_us-gaap_CashAndCashEquivalentsAxis_019ebe77-3c2d-7c09-bd54-526a7f996e5b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_019ebe77-3c2d-7c09-bd54-526a7f996e5b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CashAndCashEquivalentsAxis_019ebe77-3c2d-7c09-bd54-526a7f996e5b" xlink:to="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_019ebe77-3c2d-7c09-bd54-526a7f996e5b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_019ebe77-3c2d-741d-bbed-71a24d117412" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CashAndCashEquivalentsAxis_019ebe77-3c2d-7c09-bd54-526a7f996e5b" xlink:to="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_019ebe77-3c2d-741d-bbed-71a24d117412" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CertificatesOfDepositMember_019ebe77-3c2d-75f8-b5c5-3cc4b5c937ab" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CertificatesOfDepositMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_019ebe77-3c2d-741d-bbed-71a24d117412" xlink:to="loc_us-gaap_CertificatesOfDepositMember_019ebe77-3c2d-75f8-b5c5-3cc4b5c937ab" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BankTimeDepositsMember_019ebe77-3c2d-76b8-b06c-dc44d90b60c8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BankTimeDepositsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_019ebe77-3c2d-741d-bbed-71a24d117412" xlink:to="loc_us-gaap_BankTimeDepositsMember_019ebe77-3c2d-76b8-b06c-dc44d90b60c8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_MarketableSecuritiesMaturityPeriod_019ebe77-3c2d-7804-aaa7-23e5052d20ce" xlink:href="fn-20260626.xsd#fn_MarketableSecuritiesMaturityPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_CashCashEquivalentsAndMarketableSecuritiesLineItems_019ebe77-3c2d-7b71-afba-76b7d6b757db" xlink:to="loc_fn_MarketableSecuritiesMaturityPeriod_019ebe77-3c2d-7804-aaa7-23e5052d20ce" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_EffectiveInterestRateOnShortTermBankDeposits_019ebe77-3c2d-7793-b022-81ef41ec34c0" xlink:href="fn-20260626.xsd#fn_EffectiveInterestRateOnShortTermBankDeposits"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_CashCashEquivalentsAndMarketableSecuritiesLineItems_019ebe77-3c2d-7b71-afba-76b7d6b757db" xlink:to="loc_fn_EffectiveInterestRateOnShortTermBankDeposits_019ebe77-3c2d-7793-b022-81ef41ec34c0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtSecurities_019ebe77-3c2d-79df-a39e-2201cba0216c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleSecuritiesDebtSecurities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_CashCashEquivalentsAndMarketableSecuritiesLineItems_019ebe77-3c2d-7b71-afba-76b7d6b757db" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtSecurities_019ebe77-3c2d-79df-a39e-2201cba0216c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_PercentageOfCashAndCashEquivalentsHeldByParentCompany_019ebe77-3c2d-71bb-9b1f-1529b23d2b77" xlink:href="fn-20260626.xsd#fn_PercentageOfCashAndCashEquivalentsHeldByParentCompany"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_CashCashEquivalentsAndMarketableSecuritiesLineItems_019ebe77-3c2d-7b71-afba-76b7d6b757db" xlink:to="loc_fn_PercentageOfCashAndCashEquivalentsHeldByParentCompany_019ebe77-3c2d-71bb-9b1f-1529b23d2b77" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleAllowanceForCreditLossWriteoff_019ebe77-3c2d-741c-bcd2-ce7f27f57bc0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleAllowanceForCreditLossWriteoff"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_CashCashEquivalentsAndMarketableSecuritiesLineItems_019ebe77-3c2d-7b71-afba-76b7d6b757db" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleAllowanceForCreditLossWriteoff_019ebe77-3c2d-741c-bcd2-ce7f27f57bc0" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/CashcashequivalentsandshortterminvestmentsSummaryofCostandEstimatedFairValueofShorttermInvestmentsClassifiedasAvailableforSaleSecuritiesDetails" xlink:type="simple" xlink:href="fn-20260626.xsd#CashcashequivalentsandshortterminvestmentsSummaryofCostandEstimatedFairValueofShorttermInvestmentsClassifiedasAvailableforSaleSecuritiesDetails"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/CashcashequivalentsandshortterminvestmentsSummaryofCostandEstimatedFairValueofShorttermInvestmentsClassifiedasAvailableforSaleSecuritiesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_fn_InvestmentsClassifiedByContractualMaturityDateLineItems_019ebe77-3c2d-7824-8223-62a2515860e6" xlink:href="fn-20260626.xsd#fn_InvestmentsClassifiedByContractualMaturityDateLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_InvestmentsClassifiedByContractualMaturityDateTable_019ebe77-3c2d-75ae-b354-94d4dfaa9812" xlink:href="fn-20260626.xsd#fn_InvestmentsClassifiedByContractualMaturityDateTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_fn_InvestmentsClassifiedByContractualMaturityDateLineItems_019ebe77-3c2d-7824-8223-62a2515860e6" xlink:to="loc_fn_InvestmentsClassifiedByContractualMaturityDateTable_019ebe77-3c2d-75ae-b354-94d4dfaa9812" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByMeasurementBasisAxis_019ebe77-3c2d-789e-b2f2-8b30b250f00b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByMeasurementBasisAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_fn_InvestmentsClassifiedByContractualMaturityDateTable_019ebe77-3c2d-75ae-b354-94d4dfaa9812" xlink:to="loc_us-gaap_FairValueByMeasurementBasisAxis_019ebe77-3c2d-789e-b2f2-8b30b250f00b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_019ebe77-3c2d-789e-b2f2-8b30b250f00b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PortionAtFairValueFairValueDisclosureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByMeasurementBasisAxis_019ebe77-3c2d-789e-b2f2-8b30b250f00b" xlink:to="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_019ebe77-3c2d-789e-b2f2-8b30b250f00b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueDisclosureItemAmountsDomain_019ebe77-3c2d-7aca-a3e5-520bea7ae48b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueDisclosureItemAmountsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByMeasurementBasisAxis_019ebe77-3c2d-789e-b2f2-8b30b250f00b" xlink:to="loc_us-gaap_FairValueDisclosureItemAmountsDomain_019ebe77-3c2d-7aca-a3e5-520bea7ae48b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_019ebe77-3c2d-7de6-8f97-e969079f17d4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PortionAtFairValueFairValueDisclosureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueDisclosureItemAmountsDomain_019ebe77-3c2d-7aca-a3e5-520bea7ae48b" xlink:to="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_019ebe77-3c2d-7de6-8f97-e969079f17d4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CarryingReportedAmountFairValueDisclosureMember_019ebe77-3c2d-7538-b61f-2d46e403506c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CarryingReportedAmountFairValueDisclosureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_019ebe77-3c2d-7de6-8f97-e969079f17d4" xlink:to="loc_us-gaap_CarryingReportedAmountFairValueDisclosureMember_019ebe77-3c2d-7538-b61f-2d46e403506c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EstimateOfFairValueFairValueDisclosureMember_019ebe77-3c2d-78d2-97bd-c93a18e312c9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EstimateOfFairValueFairValueDisclosureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_019ebe77-3c2d-7de6-8f97-e969079f17d4" xlink:to="loc_us-gaap_EstimateOfFairValueFairValueDisclosureMember_019ebe77-3c2d-78d2-97bd-c93a18e312c9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost_019ebe77-3c2d-7605-8f80-601fa55a8597" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_InvestmentsClassifiedByContractualMaturityDateLineItems_019ebe77-3c2d-7824-8223-62a2515860e6" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost_019ebe77-3c2d-7605-8f80-601fa55a8597" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost_019ebe77-3c2d-7053-a650-29e4234aba69" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_InvestmentsClassifiedByContractualMaturityDateLineItems_019ebe77-3c2d-7824-8223-62a2515860e6" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost_019ebe77-3c2d-7053-a650-29e4234aba69" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_019ebe77-3c2d-71b8-b7a7-baa4e78caf62" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_InvestmentsClassifiedByContractualMaturityDateLineItems_019ebe77-3c2d-7824-8223-62a2515860e6" xlink:to="loc_us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_019ebe77-3c2d-71b8-b7a7-baa4e78caf62" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue_019ebe77-3c2d-7a49-a8cf-1730c1431ee5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_InvestmentsClassifiedByContractualMaturityDateLineItems_019ebe77-3c2d-7824-8223-62a2515860e6" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue_019ebe77-3c2d-7a49-a8cf-1730c1431ee5" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue_019ebe77-3c2d-7251-8542-7edcd8ebf342" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_InvestmentsClassifiedByContractualMaturityDateLineItems_019ebe77-3c2d-7824-8223-62a2515860e6" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue_019ebe77-3c2d-7251-8542-7edcd8ebf342" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MarketableSecuritiesCurrent_019ebe77-3c2d-7313-8a1a-7ad7b532560f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MarketableSecuritiesCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_InvestmentsClassifiedByContractualMaturityDateLineItems_019ebe77-3c2d-7824-8223-62a2515860e6" xlink:to="loc_us-gaap_MarketableSecuritiesCurrent_019ebe77-3c2d-7313-8a1a-7ad7b532560f" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/NonmarketableequitysecuritiesNarrativeDetails" xlink:type="simple" xlink:href="fn-20260626.xsd#NonmarketableequitysecuritiesNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/NonmarketableequitysecuritiesNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MarketableSecuritiesLineItems_019fcff7-35bf-7e19-ad83-bed81248c701" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MarketableSecuritiesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MarketableSecuritiesTable_019fcff7-35bf-77d1-bb29-0f5717b8ec22" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MarketableSecuritiesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_MarketableSecuritiesLineItems_019fcff7-35bf-7e19-ad83-bed81248c701" xlink:to="loc_us-gaap_MarketableSecuritiesTable_019fcff7-35bf-77d1-bb29-0f5717b8ec22" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019fcff7-35bf-7040-a6ac-517a4e044c1e" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_MarketableSecuritiesTable_019fcff7-35bf-77d1-bb29-0f5717b8ec22" xlink:to="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019fcff7-35bf-7040-a6ac-517a4e044c1e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_019fcff7-35bf-7040-a6ac-517a4e044c1e_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019fcff7-35bf-7040-a6ac-517a4e044c1e" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_019fcff7-35bf-7040-a6ac-517a4e044c1e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_019fcff7-35bf-72b3-85c0-cfad39edb81c" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019fcff7-35bf-7040-a6ac-517a4e044c1e" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_019fcff7-35bf-72b3-85c0-cfad39edb81c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_RaytekSemiconductorInc.RaytekMember_019fcff7-961d-7df3-ae61-55e9af48ca8b" xlink:href="fn-20260626.xsd#fn_RaytekSemiconductorInc.RaytekMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_019fcff7-35bf-72b3-85c0-cfad39edb81c" xlink:to="loc_fn_RaytekSemiconductorInc.RaytekMember_019fcff7-961d-7df3-ae61-55e9af48ca8b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityOwnershipPercentageExcludingConsolidatedEntityAndEquityMethodInvestee_019fcff7-35bf-7ecf-bcf0-7d1dcbcaff86" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityOwnershipPercentageExcludingConsolidatedEntityAndEquityMethodInvestee"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MarketableSecuritiesLineItems_019fcff7-35bf-7e19-ad83-bed81248c701" xlink:to="loc_us-gaap_EquityOwnershipPercentageExcludingConsolidatedEntityAndEquityMethodInvestee_019fcff7-35bf-7ecf-bcf0-7d1dcbcaff86" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesWithoutReadilyDeterminableFairValueAmount_019fcff8-0c06-70d5-9ae9-de2ed0bede23" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquitySecuritiesWithoutReadilyDeterminableFairValueAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MarketableSecuritiesLineItems_019fcff7-35bf-7e19-ad83-bed81248c701" xlink:to="loc_us-gaap_EquitySecuritiesWithoutReadilyDeterminableFairValueAmount_019fcff8-0c06-70d5-9ae9-de2ed0bede23" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesWithoutReadilyDeterminableFairValueUpwardPriceAdjustmentAnnualAmount_019fee62-d8d5-71de-8c7e-9a1d0f0080a5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquitySecuritiesWithoutReadilyDeterminableFairValueUpwardPriceAdjustmentAnnualAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MarketableSecuritiesLineItems_019fcff7-35bf-7e19-ad83-bed81248c701" xlink:to="loc_us-gaap_EquitySecuritiesWithoutReadilyDeterminableFairValueUpwardPriceAdjustmentAnnualAmount_019fee62-d8d5-71de-8c7e-9a1d0f0080a5" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/FairvalueoffinancialinstrumentsScheduleofFinancialInstrumentsMeasuredatFairValueonRecurringBasisDetails" xlink:type="simple" xlink:href="fn-20260626.xsd#FairvalueoffinancialinstrumentsScheduleofFinancialInstrumentsMeasuredatFairValueonRecurringBasisDetails"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/FairvalueoffinancialinstrumentsScheduleofFinancialInstrumentsMeasuredatFairValueonRecurringBasisDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019ebe77-3c2d-75ff-89a6-bc03683d992b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019ebe77-3c2d-7cb6-8dab-e95e931ba3c5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019ebe77-3c2d-75ff-89a6-bc03683d992b" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019ebe77-3c2d-7cb6-8dab-e95e931ba3c5" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019ebe77-3c2d-7189-a6e6-50926aea996b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019ebe77-3c2d-7cb6-8dab-e95e931ba3c5" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019ebe77-3c2d-7189-a6e6-50926aea996b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019ebe77-3c2d-7189-a6e6-50926aea996b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019ebe77-3c2d-7189-a6e6-50926aea996b" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019ebe77-3c2d-7189-a6e6-50926aea996b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019ebe77-3c2d-7028-9e9a-faa0c592d354" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019ebe77-3c2d-7189-a6e6-50926aea996b" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019ebe77-3c2d-7028-9e9a-faa0c592d354" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel1Member_019ebe77-3c2d-770b-a7d4-5b3d18f7f393" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel1Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019ebe77-3c2d-7028-9e9a-faa0c592d354" xlink:to="loc_us-gaap_FairValueInputsLevel1Member_019ebe77-3c2d-770b-a7d4-5b3d18f7f393" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel2Member_019ebe77-3c2d-7e7e-a43d-fa3edd604707" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel2Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019ebe77-3c2d-7028-9e9a-faa0c592d354" xlink:to="loc_us-gaap_FairValueInputsLevel2Member_019ebe77-3c2d-7e7e-a43d-fa3edd604707" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel3Member_019ebe77-3c2d-7493-bee6-a17a2a7ee663" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel3Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019ebe77-3c2d-7028-9e9a-faa0c592d354" xlink:to="loc_us-gaap_FairValueInputsLevel3Member_019ebe77-3c2d-7493-bee6-a17a2a7ee663" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeAxis_019ebe77-3c2d-76ef-9637-76ae772400aa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019ebe77-3c2d-7cb6-8dab-e95e931ba3c5" xlink:to="loc_us-gaap_InvestmentTypeAxis_019ebe77-3c2d-76ef-9637-76ae772400aa" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_019ebe77-3c2d-76ef-9637-76ae772400aa_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentTypeAxis_019ebe77-3c2d-76ef-9637-76ae772400aa" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_019ebe77-3c2d-76ef-9637-76ae772400aa_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_019ebe77-3c2d-7056-bd42-97e8373d4462" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentTypeAxis_019ebe77-3c2d-76ef-9637-76ae772400aa" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_019ebe77-3c2d-7056-bd42-97e8373d4462" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashEquivalentsMember_019ebe77-3c2d-72b5-99b2-58ee7dd8194a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashEquivalentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ebe77-3c2d-7056-bd42-97e8373d4462" xlink:to="loc_us-gaap_CashEquivalentsMember_019ebe77-3c2d-72b5-99b2-58ee7dd8194a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestBearingDepositsMember_019ebe77-3c2d-799c-af7a-e6692d405d88" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestBearingDepositsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ebe77-3c2d-7056-bd42-97e8373d4462" xlink:to="loc_us-gaap_InterestBearingDepositsMember_019ebe77-3c2d-799c-af7a-e6692d405d88" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateDebtSecuritiesMember_019ebe77-3c2d-78aa-b54a-2ffb8799e8e8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CorporateDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ebe77-3c2d-7056-bd42-97e8373d4462" xlink:to="loc_us-gaap_CorporateDebtSecuritiesMember_019ebe77-3c2d-78aa-b54a-2ffb8799e8e8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_USTreasurySecuritiesAndUSGovernmentAndAgencySecuritiesMember_019ebe77-3c2d-7830-98ca-47361f9d2a4b" xlink:href="fn-20260626.xsd#fn_USTreasurySecuritiesAndUSGovernmentAndAgencySecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ebe77-3c2d-7056-bd42-97e8373d4462" xlink:to="loc_fn_USTreasurySecuritiesAndUSGovernmentAndAgencySecuritiesMember_019ebe77-3c2d-7830-98ca-47361f9d2a4b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_019ebe77-3c2d-7ef1-9cdc-dc1fb4528054" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019ebe77-3c2d-7cb6-8dab-e95e931ba3c5" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_019ebe77-3c2d-7ef1-9cdc-dc1fb4528054" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019ebe77-3c2d-7ef1-9cdc-dc1fb4528054_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019ebe77-3c2d-7ef1-9cdc-dc1fb4528054" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019ebe77-3c2d-7ef1-9cdc-dc1fb4528054_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019ebe77-3c2d-724c-a875-593e1f0ce893" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019ebe77-3c2d-7ef1-9cdc-dc1fb4528054" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019ebe77-3c2d-724c-a875-593e1f0ce893" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignExchangeForwardMember_019ebe77-3c2d-719a-a10c-6ef297609713" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignExchangeForwardMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019ebe77-3c2d-724c-a875-593e1f0ce893" xlink:to="loc_us-gaap_ForeignExchangeForwardMember_019ebe77-3c2d-719a-a10c-6ef297609713" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CurrencyAxis_019ebe77-3c2d-7757-9ff5-745bb1098831" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_CurrencyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019ebe77-3c2d-7cb6-8dab-e95e931ba3c5" xlink:to="loc_srt_CurrencyAxis_019ebe77-3c2d-7757-9ff5-745bb1098831" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_currency_AllCurrenciesDomain_019ebe77-3c2d-7757-9ff5-745bb1098831_default" xlink:href="https://xbrl.sec.gov/currency/2026/currency-2026.xsd#currency_AllCurrenciesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_CurrencyAxis_019ebe77-3c2d-7757-9ff5-745bb1098831" xlink:to="loc_currency_AllCurrenciesDomain_019ebe77-3c2d-7757-9ff5-745bb1098831_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_currency_AllCurrenciesDomain_019ebe77-3c2d-7251-b68b-980007e48d80" xlink:href="https://xbrl.sec.gov/currency/2026/currency-2026.xsd#currency_AllCurrenciesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_CurrencyAxis_019ebe77-3c2d-7757-9ff5-745bb1098831" xlink:to="loc_currency_AllCurrenciesDomain_019ebe77-3c2d-7251-b68b-980007e48d80" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_currency_CAD_019ebe77-3c2d-7eab-8399-cfe4f9dce511" xlink:href="https://xbrl.sec.gov/currency/2026/currency-2026.xsd#currency_CAD"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_currency_AllCurrenciesDomain_019ebe77-3c2d-7251-b68b-980007e48d80" xlink:to="loc_currency_CAD_019ebe77-3c2d-7eab-8399-cfe4f9dce511" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsFairValueDisclosureAbstract_019ebe77-3c2d-7b7f-b742-9cfe5896176e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsFairValueDisclosureAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019ebe77-3c2d-75ff-89a6-bc03683d992b" xlink:to="loc_us-gaap_AssetsFairValueDisclosureAbstract_019ebe77-3c2d-7b7f-b742-9cfe5896176e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentsFairValueDisclosure_019ebe77-3c2d-7163-889f-400acb9f1028" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_019ebe77-3c2d-7b7f-b742-9cfe5896176e" xlink:to="loc_us-gaap_InvestmentsFairValueDisclosure_019ebe77-3c2d-7163-889f-400acb9f1028" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetCurrentStatementOfFinancialPositionExtensibleEnumeration_019ebe77-3c2d-7033-be93-5da2a99ba4d6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssetCurrentStatementOfFinancialPositionExtensibleEnumeration"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_019ebe77-3c2d-7b7f-b742-9cfe5896176e" xlink:to="loc_us-gaap_DerivativeAssetCurrentStatementOfFinancialPositionExtensibleEnumeration_019ebe77-3c2d-7033-be93-5da2a99ba4d6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetsCurrent_019ebe77-3c2d-7f0f-a850-8fa960025536" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssetsCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_019ebe77-3c2d-7b7f-b742-9cfe5896176e" xlink:to="loc_us-gaap_DerivativeAssetsCurrent_019ebe77-3c2d-7f0f-a850-8fa960025536" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsFairValueDisclosure_019ebe77-3c2d-7fcb-b5a5-b73385206d91" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_019ebe77-3c2d-7b7f-b742-9cfe5896176e" xlink:to="loc_us-gaap_AssetsFairValueDisclosure_019ebe77-3c2d-7fcb-b5a5-b73385206d91" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_019ebe77-3c2d-7fe5-9777-969f4536e6a5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesFairValueDisclosureAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019ebe77-3c2d-75ff-89a6-bc03683d992b" xlink:to="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_019ebe77-3c2d-7fe5-9777-969f4536e6a5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilityCurrentStatementOfFinancialPositionExtensibleEnumeration_019ebe77-3c2d-78df-bdd3-e791759c878b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLiabilityCurrentStatementOfFinancialPositionExtensibleEnumeration"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_019ebe77-3c2d-7fe5-9777-969f4536e6a5" xlink:to="loc_us-gaap_DerivativeLiabilityCurrentStatementOfFinancialPositionExtensibleEnumeration_019ebe77-3c2d-78df-bdd3-e791759c878b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilitiesCurrent_019ebe77-3c2d-7d80-9a36-649bb8012fd8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLiabilitiesCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_019ebe77-3c2d-7fe5-9777-969f4536e6a5" xlink:to="loc_us-gaap_DerivativeLiabilitiesCurrent_019ebe77-3c2d-7d80-9a36-649bb8012fd8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesFairValueDisclosure_019ebe77-3c2d-793c-89f3-2f5338e8ca8b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_019ebe77-3c2d-7fe5-9777-969f4536e6a5" xlink:to="loc_us-gaap_LiabilitiesFairValueDisclosure_019ebe77-3c2d-793c-89f3-2f5338e8ca8b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetNotionalAmount_019ebe77-3c2d-73c6-bf4b-5695d85f45fd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssetNotionalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019ebe77-3c2d-75ff-89a6-bc03683d992b" xlink:to="loc_us-gaap_DerivativeAssetNotionalAmount_019ebe77-3c2d-73c6-bf4b-5695d85f45fd" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilityNotionalAmount_019ebe77-3c2d-76eb-a47b-4ae3b353205a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLiabilityNotionalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019ebe77-3c2d-75ff-89a6-bc03683d992b" xlink:to="loc_us-gaap_DerivativeLiabilityNotionalAmount_019ebe77-3c2d-76eb-a47b-4ae3b353205a" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/FairvalueoffinancialinstrumentsAdditionalInformationDetails" xlink:type="simple" xlink:href="fn-20260626.xsd#FairvalueoffinancialinstrumentsAdditionalInformationDetails"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/FairvalueoffinancialinstrumentsAdditionalInformationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLineItems_019ebe77-3c2d-7cc1-875b-c92bdffbbd42" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeTable_019ebe77-3c2d-79ab-8a04-e3ba92ee82b8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeLineItems_019ebe77-3c2d-7cc1-875b-c92bdffbbd42" xlink:to="loc_us-gaap_DerivativeTable_019ebe77-3c2d-79ab-8a04-e3ba92ee82b8" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_019ebe77-3c2d-7eee-8d2c-4fe0ffa8251e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_019ebe77-3c2d-79ab-8a04-e3ba92ee82b8" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_019ebe77-3c2d-7eee-8d2c-4fe0ffa8251e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019ebe77-3c2d-7eee-8d2c-4fe0ffa8251e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019ebe77-3c2d-7eee-8d2c-4fe0ffa8251e" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019ebe77-3c2d-7eee-8d2c-4fe0ffa8251e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019ebe77-3c2d-7970-b563-afabdb82fb31" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019ebe77-3c2d-7eee-8d2c-4fe0ffa8251e" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019ebe77-3c2d-7970-b563-afabdb82fb31" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignExchangeForwardMember_019ebe77-3c2d-75fc-af47-0fc16f75e238" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignExchangeForwardMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019ebe77-3c2d-7970-b563-afabdb82fb31" xlink:to="loc_us-gaap_ForeignExchangeForwardMember_019ebe77-3c2d-75fc-af47-0fc16f75e238" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationAxis_019ebe77-3c2d-7927-ae99-e49fa11fdf81" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgingDesignationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_019ebe77-3c2d-79ab-8a04-e3ba92ee82b8" xlink:to="loc_us-gaap_HedgingDesignationAxis_019ebe77-3c2d-7927-ae99-e49fa11fdf81" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain_019ebe77-3c2d-7927-ae99-e49fa11fdf81_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_HedgingDesignationAxis_019ebe77-3c2d-7927-ae99-e49fa11fdf81" xlink:to="loc_us-gaap_HedgingDesignationDomain_019ebe77-3c2d-7927-ae99-e49fa11fdf81_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain_019ebe77-3c2d-70ab-9930-1498b6a868d0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_HedgingDesignationAxis_019ebe77-3c2d-7927-ae99-e49fa11fdf81" xlink:to="loc_us-gaap_HedgingDesignationDomain_019ebe77-3c2d-70ab-9930-1498b6a868d0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DesignatedAsHedgingInstrumentMember_019ebe77-3c2d-7df2-bfa5-db3dc8a679b5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DesignatedAsHedgingInstrumentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingDesignationDomain_019ebe77-3c2d-70ab-9930-1498b6a868d0" xlink:to="loc_us-gaap_DesignatedAsHedgingInstrumentMember_019ebe77-3c2d-7df2-bfa5-db3dc8a679b5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NondesignatedMember_019ebe77-3c2d-7e7f-a25a-9b63e97412ed" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NondesignatedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingDesignationDomain_019ebe77-3c2d-70ab-9930-1498b6a868d0" xlink:to="loc_us-gaap_NondesignatedMember_019ebe77-3c2d-7e7f-a25a-9b63e97412ed" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CurrencyAxis_019ebe77-3c2d-714e-9372-d0fdc97c4d36" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_CurrencyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_019ebe77-3c2d-79ab-8a04-e3ba92ee82b8" xlink:to="loc_srt_CurrencyAxis_019ebe77-3c2d-714e-9372-d0fdc97c4d36" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_currency_AllCurrenciesDomain_019ebe77-3c2d-714e-9372-d0fdc97c4d36_default" xlink:href="https://xbrl.sec.gov/currency/2026/currency-2026.xsd#currency_AllCurrenciesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_CurrencyAxis_019ebe77-3c2d-714e-9372-d0fdc97c4d36" xlink:to="loc_currency_AllCurrenciesDomain_019ebe77-3c2d-714e-9372-d0fdc97c4d36_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_currency_AllCurrenciesDomain_019ebe77-3c2d-7e3b-9380-6a0d0e79349b" xlink:href="https://xbrl.sec.gov/currency/2026/currency-2026.xsd#currency_AllCurrenciesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_CurrencyAxis_019ebe77-3c2d-714e-9372-d0fdc97c4d36" xlink:to="loc_currency_AllCurrenciesDomain_019ebe77-3c2d-7e3b-9380-6a0d0e79349b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_currency_THB_019ebe77-3c2d-71e6-85b7-ff1ac3926480" xlink:href="https://xbrl.sec.gov/currency/2026/currency-2026.xsd#currency_THB"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_currency_AllCurrenciesDomain_019ebe77-3c2d-7e3b-9380-6a0d0e79349b" xlink:to="loc_currency_THB_019ebe77-3c2d-71e6-85b7-ff1ac3926480" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_currency_CAD_019ebe77-3c2d-7034-928b-120e32f8d3f7" xlink:href="https://xbrl.sec.gov/currency/2026/currency-2026.xsd#currency_CAD"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_currency_AllCurrenciesDomain_019ebe77-3c2d-7e3b-9380-6a0d0e79349b" xlink:to="loc_currency_CAD_019ebe77-3c2d-7034-928b-120e32f8d3f7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NumberOfForeignCurrencyDerivativesHeld_019ebe77-3c2d-7e49-9677-8ff839fd1d64" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NumberOfForeignCurrencyDerivativesHeld"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_019ebe77-3c2d-7cc1-875b-c92bdffbbd42" xlink:to="loc_us-gaap_NumberOfForeignCurrencyDerivativesHeld_019ebe77-3c2d-7e49-9677-8ff839fd1d64" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeNotionalAmount_019ebe77-3c2d-76d3-ae64-1a8332b918e2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeNotionalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_019ebe77-3c2d-7cc1-875b-c92bdffbbd42" xlink:to="loc_us-gaap_DerivativeNotionalAmount_019ebe77-3c2d-76d3-ae64-1a8332b918e2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilityNotionalAmount_019ebe77-3c2d-7a6c-aca2-c07d633ccfbc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLiabilityNotionalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_019ebe77-3c2d-7cc1-875b-c92bdffbbd42" xlink:to="loc_us-gaap_DerivativeLiabilityNotionalAmount_019ebe77-3c2d-7a6c-aca2-c07d633ccfbc" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossReclassificationFromAccumulatedOCIToIncomeEstimatedNetAmountToBeTransferred_019ebe77-3c2d-7529-8368-df2551e7ef8a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentsGainLossReclassificationFromAccumulatedOCIToIncomeEstimatedNetAmountToBeTransferred"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_019ebe77-3c2d-7cc1-875b-c92bdffbbd42" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossReclassificationFromAccumulatedOCIToIncomeEstimatedNetAmountToBeTransferred_019ebe77-3c2d-7529-8368-df2551e7ef8a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnrealizedGainLossOnDerivatives_019ebe77-3c2d-7641-9ff6-077e2f80996e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_UnrealizedGainLossOnDerivatives"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_019ebe77-3c2d-7cc1-875b-c92bdffbbd42" xlink:to="loc_us-gaap_UnrealizedGainLossOnDerivatives_019ebe77-3c2d-7641-9ff6-077e2f80996e" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/FairvalueoffinancialinstrumentsScheduleImpactsofDerivativeGainLossofCashFlowHedgesDetails" xlink:type="simple" xlink:href="fn-20260626.xsd#FairvalueoffinancialinstrumentsScheduleImpactsofDerivativeGainLossofCashFlowHedgesDetails"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/FairvalueoffinancialinstrumentsScheduleImpactsofDerivativeGainLossofCashFlowHedgesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsAbstract_019ebe77-3c2d-7723-9b4e-d6378ddee52e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsAbstract"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsTable_019ebe77-3c2d-7d2a-81bc-b4b5415e16cc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsAbstract_019ebe77-3c2d-7723-9b4e-d6378ddee52e" xlink:to="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsTable_019ebe77-3c2d-7d2a-81bc-b4b5415e16cc" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_019ebe77-3c2d-7240-a4c6-6416693c7cd2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsTable_019ebe77-3c2d-7d2a-81bc-b4b5415e16cc" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_019ebe77-3c2d-7240-a4c6-6416693c7cd2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019ebe77-3c2d-7240-a4c6-6416693c7cd2_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019ebe77-3c2d-7240-a4c6-6416693c7cd2" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019ebe77-3c2d-7240-a4c6-6416693c7cd2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019ebe77-3c2d-758b-9472-851d6fcc962b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019ebe77-3c2d-7240-a4c6-6416693c7cd2" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019ebe77-3c2d-758b-9472-851d6fcc962b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignExchangeForwardMember_019ebe77-3c2d-7e33-ba28-b47545eb05ff" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignExchangeForwardMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019ebe77-3c2d-758b-9472-851d6fcc962b" xlink:to="loc_us-gaap_ForeignExchangeForwardMember_019ebe77-3c2d-7e33-ba28-b47545eb05ff" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeBalanceAxis_019ebe77-3c2d-741b-bfdb-d78e05ca863c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeBalanceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsTable_019ebe77-3c2d-7d2a-81bc-b4b5415e16cc" xlink:to="loc_us-gaap_OtherComprehensiveIncomeBalanceAxis_019ebe77-3c2d-741b-bfdb-d78e05ca863c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementOfIncomeLocationBalanceAxis_019ebe77-3c2d-7a66-b29d-5bf115ed3d04" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementOfIncomeLocationBalanceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsTable_019ebe77-3c2d-7d2a-81bc-b4b5415e16cc" xlink:to="loc_us-gaap_StatementOfIncomeLocationBalanceAxis_019ebe77-3c2d-7a66-b29d-5bf115ed3d04" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_DerivativesGainLossRecognizedIntoOtherComprehensiveIncomeAbstract_019ebe77-3c2d-75fd-8b90-e12bf2136cd7" xlink:href="fn-20260626.xsd#fn_DerivativesGainLossRecognizedIntoOtherComprehensiveIncomeAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsAbstract_019ebe77-3c2d-7723-9b4e-d6378ddee52e" xlink:to="loc_fn_DerivativesGainLossRecognizedIntoOtherComprehensiveIncomeAbstract_019ebe77-3c2d-75fd-8b90-e12bf2136cd7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax_019ebe77-3c2d-74aa-bd49-6c05258aecf0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_DerivativesGainLossRecognizedIntoOtherComprehensiveIncomeAbstract_019ebe77-3c2d-75fd-8b90-e12bf2136cd7" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax_019ebe77-3c2d-74aa-bd49-6c05258aecf0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_DerivativesGainLossReclassifiedFromOtherComprehensiveIncomeIntoEarningsAbstract_019ebe77-3c2d-7862-b59b-df31f11d5c41" xlink:href="fn-20260626.xsd#fn_DerivativesGainLossReclassifiedFromOtherComprehensiveIncomeIntoEarningsAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsAbstract_019ebe77-3c2d-7723-9b4e-d6378ddee52e" xlink:to="loc_fn_DerivativesGainLossReclassifiedFromOtherComprehensiveIncomeIntoEarningsAbstract_019ebe77-3c2d-7862-b59b-df31f11d5c41" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax_019ebe77-3c2d-7604-9a4f-4fd9440d8f13" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_DerivativesGainLossReclassifiedFromOtherComprehensiveIncomeIntoEarningsAbstract_019ebe77-3c2d-7862-b59b-df31f11d5c41" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax_019ebe77-3c2d-7604-9a4f-4fd9440d8f13" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationBeforeTaxParent_019ebe77-3c2d-7dc5-8657-54c33b5cb803" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationBeforeTaxParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsAbstract_019ebe77-3c2d-7723-9b4e-d6378ddee52e" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationBeforeTaxParent_019ebe77-3c2d-7dc5-8657-54c33b5cb803" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/FairvalueoffinancialinstrumentsScheduleImpactsofDerivativeGainLossofCashFlowHedgesDetails_1" xlink:type="simple" xlink:href="fn-20260626.xsd#FairvalueoffinancialinstrumentsScheduleImpactsofDerivativeGainLossofCashFlowHedgesDetails_1"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/FairvalueoffinancialinstrumentsScheduleImpactsofDerivativeGainLossofCashFlowHedgesDetails_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsAbstract_019ebe77-3c2d-7723-9b4e-d6378ddee52e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsAbstract"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsTable_019ebe77-3c2d-7d2a-81bc-b4b5415e16cc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsAbstract_019ebe77-3c2d-7723-9b4e-d6378ddee52e" xlink:to="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsTable_019ebe77-3c2d-7d2a-81bc-b4b5415e16cc" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_019ebe77-3c2d-7240-a4c6-6416693c7cd2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsTable_019ebe77-3c2d-7d2a-81bc-b4b5415e16cc" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_019ebe77-3c2d-7240-a4c6-6416693c7cd2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019ebe77-3c2d-7240-a4c6-6416693c7cd2_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019ebe77-3c2d-7240-a4c6-6416693c7cd2" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019ebe77-3c2d-7240-a4c6-6416693c7cd2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019ebe77-3c2d-758b-9472-851d6fcc962b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019ebe77-3c2d-7240-a4c6-6416693c7cd2" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019ebe77-3c2d-758b-9472-851d6fcc962b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignExchangeForwardMember_019ebe77-3c2d-7e33-ba28-b47545eb05ff" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignExchangeForwardMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019ebe77-3c2d-758b-9472-851d6fcc962b" xlink:to="loc_us-gaap_ForeignExchangeForwardMember_019ebe77-3c2d-7e33-ba28-b47545eb05ff" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_DerivativesGainLossRecognizedIntoOtherComprehensiveIncomeAbstract_019ebe77-3c2d-75fd-8b90-e12bf2136cd7" xlink:href="fn-20260626.xsd#fn_DerivativesGainLossRecognizedIntoOtherComprehensiveIncomeAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsAbstract_019ebe77-3c2d-7723-9b4e-d6378ddee52e" xlink:to="loc_fn_DerivativesGainLossRecognizedIntoOtherComprehensiveIncomeAbstract_019ebe77-3c2d-75fd-8b90-e12bf2136cd7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax_019ebe77-3c2d-74aa-bd49-6c05258aecf0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_DerivativesGainLossRecognizedIntoOtherComprehensiveIncomeAbstract_019ebe77-3c2d-75fd-8b90-e12bf2136cd7" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax_019ebe77-3c2d-74aa-bd49-6c05258aecf0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_DerivativesGainLossReclassifiedFromOtherComprehensiveIncomeIntoEarningsAbstract_019ebe77-3c2d-7862-b59b-df31f11d5c41" xlink:href="fn-20260626.xsd#fn_DerivativesGainLossReclassifiedFromOtherComprehensiveIncomeIntoEarningsAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsAbstract_019ebe77-3c2d-7723-9b4e-d6378ddee52e" xlink:to="loc_fn_DerivativesGainLossReclassifiedFromOtherComprehensiveIncomeIntoEarningsAbstract_019ebe77-3c2d-7862-b59b-df31f11d5c41" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax_019ebe77-3c2d-7604-9a4f-4fd9440d8f13" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_DerivativesGainLossReclassifiedFromOtherComprehensiveIncomeIntoEarningsAbstract_019ebe77-3c2d-7862-b59b-df31f11d5c41" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax_019ebe77-3c2d-7604-9a4f-4fd9440d8f13" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationBeforeTaxParent_019ebe77-3c2d-7dc5-8657-54c33b5cb803" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationBeforeTaxParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsAbstract_019ebe77-3c2d-7723-9b4e-d6378ddee52e" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationBeforeTaxParent_019ebe77-3c2d-7dc5-8657-54c33b5cb803" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/FairvalueoffinancialinstrumentsScheduleImpactsofDerivativeGainLossofCashFlowHedgesDetails_2" xlink:type="simple" xlink:href="fn-20260626.xsd#FairvalueoffinancialinstrumentsScheduleImpactsofDerivativeGainLossofCashFlowHedgesDetails_2"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/FairvalueoffinancialinstrumentsScheduleImpactsofDerivativeGainLossofCashFlowHedgesDetails_2" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsAbstract_019ebe77-3c2d-7723-9b4e-d6378ddee52e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsAbstract"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsTable_019ebe77-3c2d-7d2a-81bc-b4b5415e16cc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsAbstract_019ebe77-3c2d-7723-9b4e-d6378ddee52e" xlink:to="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsTable_019ebe77-3c2d-7d2a-81bc-b4b5415e16cc" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_019ebe77-3c2d-7240-a4c6-6416693c7cd2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsTable_019ebe77-3c2d-7d2a-81bc-b4b5415e16cc" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_019ebe77-3c2d-7240-a4c6-6416693c7cd2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019ebe77-3c2d-7240-a4c6-6416693c7cd2_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019ebe77-3c2d-7240-a4c6-6416693c7cd2" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019ebe77-3c2d-7240-a4c6-6416693c7cd2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019ebe77-3c2d-758b-9472-851d6fcc962b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019ebe77-3c2d-7240-a4c6-6416693c7cd2" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019ebe77-3c2d-758b-9472-851d6fcc962b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignExchangeForwardMember_019ebe77-3c2d-7e33-ba28-b47545eb05ff" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignExchangeForwardMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019ebe77-3c2d-758b-9472-851d6fcc962b" xlink:to="loc_us-gaap_ForeignExchangeForwardMember_019ebe77-3c2d-7e33-ba28-b47545eb05ff" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeBalanceAxis_019ebe77-3c2d-741b-bfdb-d78e05ca863c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeBalanceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsTable_019ebe77-3c2d-7d2a-81bc-b4b5415e16cc" xlink:to="loc_us-gaap_OtherComprehensiveIncomeBalanceAxis_019ebe77-3c2d-741b-bfdb-d78e05ca863c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_DerivativesGainLossRecognizedIntoOtherComprehensiveIncomeAbstract_019ebe77-3c2d-75fd-8b90-e12bf2136cd7" xlink:href="fn-20260626.xsd#fn_DerivativesGainLossRecognizedIntoOtherComprehensiveIncomeAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsAbstract_019ebe77-3c2d-7723-9b4e-d6378ddee52e" xlink:to="loc_fn_DerivativesGainLossRecognizedIntoOtherComprehensiveIncomeAbstract_019ebe77-3c2d-75fd-8b90-e12bf2136cd7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax_019ebe77-3c2d-74aa-bd49-6c05258aecf0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_DerivativesGainLossRecognizedIntoOtherComprehensiveIncomeAbstract_019ebe77-3c2d-75fd-8b90-e12bf2136cd7" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax_019ebe77-3c2d-74aa-bd49-6c05258aecf0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_DerivativesGainLossReclassifiedFromOtherComprehensiveIncomeIntoEarningsAbstract_019ebe77-3c2d-7862-b59b-df31f11d5c41" xlink:href="fn-20260626.xsd#fn_DerivativesGainLossReclassifiedFromOtherComprehensiveIncomeIntoEarningsAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsAbstract_019ebe77-3c2d-7723-9b4e-d6378ddee52e" xlink:to="loc_fn_DerivativesGainLossReclassifiedFromOtherComprehensiveIncomeIntoEarningsAbstract_019ebe77-3c2d-7862-b59b-df31f11d5c41" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax_019ebe77-3c2d-7604-9a4f-4fd9440d8f13" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_DerivativesGainLossReclassifiedFromOtherComprehensiveIncomeIntoEarningsAbstract_019ebe77-3c2d-7862-b59b-df31f11d5c41" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax_019ebe77-3c2d-7604-9a4f-4fd9440d8f13" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationBeforeTaxParent_019ebe77-3c2d-7dc5-8657-54c33b5cb803" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationBeforeTaxParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsAbstract_019ebe77-3c2d-7723-9b4e-d6378ddee52e" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationBeforeTaxParent_019ebe77-3c2d-7dc5-8657-54c33b5cb803" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/FairvalueoffinancialinstrumentsScheduleImpactsofDerivativeGainLossofCashFlowHedgesDetails_3" xlink:type="simple" xlink:href="fn-20260626.xsd#FairvalueoffinancialinstrumentsScheduleImpactsofDerivativeGainLossofCashFlowHedgesDetails_3"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/FairvalueoffinancialinstrumentsScheduleImpactsofDerivativeGainLossofCashFlowHedgesDetails_3" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsAbstract_019ebe77-3c2d-7723-9b4e-d6378ddee52e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsAbstract"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsTable_019ebe77-3c2d-7d2a-81bc-b4b5415e16cc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsAbstract_019ebe77-3c2d-7723-9b4e-d6378ddee52e" xlink:to="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsTable_019ebe77-3c2d-7d2a-81bc-b4b5415e16cc" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_019ebe77-3c2d-7240-a4c6-6416693c7cd2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsTable_019ebe77-3c2d-7d2a-81bc-b4b5415e16cc" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_019ebe77-3c2d-7240-a4c6-6416693c7cd2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019ebe77-3c2d-7240-a4c6-6416693c7cd2_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019ebe77-3c2d-7240-a4c6-6416693c7cd2" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019ebe77-3c2d-7240-a4c6-6416693c7cd2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019ebe77-3c2d-758b-9472-851d6fcc962b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019ebe77-3c2d-7240-a4c6-6416693c7cd2" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019ebe77-3c2d-758b-9472-851d6fcc962b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignExchangeForwardMember_019ebe77-3c2d-7e33-ba28-b47545eb05ff" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignExchangeForwardMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019ebe77-3c2d-758b-9472-851d6fcc962b" xlink:to="loc_us-gaap_ForeignExchangeForwardMember_019ebe77-3c2d-7e33-ba28-b47545eb05ff" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementOfIncomeLocationBalanceAxis_019ebe77-3c2d-7a66-b29d-5bf115ed3d04" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementOfIncomeLocationBalanceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsTable_019ebe77-3c2d-7d2a-81bc-b4b5415e16cc" xlink:to="loc_us-gaap_StatementOfIncomeLocationBalanceAxis_019ebe77-3c2d-7a66-b29d-5bf115ed3d04" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_DerivativesGainLossRecognizedIntoOtherComprehensiveIncomeAbstract_019ebe77-3c2d-75fd-8b90-e12bf2136cd7" xlink:href="fn-20260626.xsd#fn_DerivativesGainLossRecognizedIntoOtherComprehensiveIncomeAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsAbstract_019ebe77-3c2d-7723-9b4e-d6378ddee52e" xlink:to="loc_fn_DerivativesGainLossRecognizedIntoOtherComprehensiveIncomeAbstract_019ebe77-3c2d-75fd-8b90-e12bf2136cd7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax_019ebe77-3c2d-74aa-bd49-6c05258aecf0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_DerivativesGainLossRecognizedIntoOtherComprehensiveIncomeAbstract_019ebe77-3c2d-75fd-8b90-e12bf2136cd7" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax_019ebe77-3c2d-74aa-bd49-6c05258aecf0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_DerivativesGainLossReclassifiedFromOtherComprehensiveIncomeIntoEarningsAbstract_019ebe77-3c2d-7862-b59b-df31f11d5c41" xlink:href="fn-20260626.xsd#fn_DerivativesGainLossReclassifiedFromOtherComprehensiveIncomeIntoEarningsAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsAbstract_019ebe77-3c2d-7723-9b4e-d6378ddee52e" xlink:to="loc_fn_DerivativesGainLossReclassifiedFromOtherComprehensiveIncomeIntoEarningsAbstract_019ebe77-3c2d-7862-b59b-df31f11d5c41" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax_019ebe77-3c2d-7604-9a4f-4fd9440d8f13" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_DerivativesGainLossReclassifiedFromOtherComprehensiveIncomeIntoEarningsAbstract_019ebe77-3c2d-7862-b59b-df31f11d5c41" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax_019ebe77-3c2d-7604-9a4f-4fd9440d8f13" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationBeforeTaxParent_019ebe77-3c2d-7dc5-8657-54c33b5cb803" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationBeforeTaxParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsAbstract_019ebe77-3c2d-7723-9b4e-d6378ddee52e" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationBeforeTaxParent_019ebe77-3c2d-7dc5-8657-54c33b5cb803" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/FairvalueoffinancialinstrumentsScheduleofDerivativeFinancialInstrumentsDetails" xlink:type="simple" xlink:href="fn-20260626.xsd#FairvalueoffinancialinstrumentsScheduleofDerivativeFinancialInstrumentsDetails"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/FairvalueoffinancialinstrumentsScheduleofDerivativeFinancialInstrumentsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLineItems_019ebe77-3c2d-7f01-b443-a5d6392fd47a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeTable_019ebe77-3c2d-7309-8685-86173276c99b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeLineItems_019ebe77-3c2d-7f01-b443-a5d6392fd47a" xlink:to="loc_us-gaap_DerivativeTable_019ebe77-3c2d-7309-8685-86173276c99b" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_019ebe77-3c2d-72e2-abc9-533b4af39f3b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_019ebe77-3c2d-7309-8685-86173276c99b" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_019ebe77-3c2d-72e2-abc9-533b4af39f3b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019ebe77-3c2d-72e2-abc9-533b4af39f3b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019ebe77-3c2d-72e2-abc9-533b4af39f3b" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019ebe77-3c2d-72e2-abc9-533b4af39f3b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019ebe77-3c2d-70fb-ad20-91fc75e50c63" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019ebe77-3c2d-72e2-abc9-533b4af39f3b" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019ebe77-3c2d-70fb-ad20-91fc75e50c63" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_ForeignCurrencyForwardAndOptionContractsMember_019ebe77-3c2d-7d3d-8367-4abf8180ced3" xlink:href="fn-20260626.xsd#fn_ForeignCurrencyForwardAndOptionContractsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019ebe77-3c2d-70fb-ad20-91fc75e50c63" xlink:to="loc_fn_ForeignCurrencyForwardAndOptionContractsMember_019ebe77-3c2d-7d3d-8367-4abf8180ced3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignExchangeForwardMember_019ebe77-3c2d-7fea-9247-c22e1fea28da" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignExchangeForwardMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019ebe77-3c2d-70fb-ad20-91fc75e50c63" xlink:to="loc_us-gaap_ForeignExchangeForwardMember_019ebe77-3c2d-7fea-9247-c22e1fea28da" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsAbstract_019ebe77-3c2d-747c-b3f6-fec905280f85" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_019ebe77-3c2d-7f01-b443-a5d6392fd47a" xlink:to="loc_us-gaap_DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsAbstract_019ebe77-3c2d-747c-b3f6-fec905280f85" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsAssetAtFairValue_019ebe77-3c2d-7911-95a3-9483fcdfc821" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsAssetAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsAbstract_019ebe77-3c2d-747c-b3f6-fec905280f85" xlink:to="loc_us-gaap_DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsAssetAtFairValue_019ebe77-3c2d-7911-95a3-9483fcdfc821" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsLiabilityAtFairValue_019ebe77-3c2d-7e39-b10b-254a5833c6fb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsLiabilityAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsAbstract_019ebe77-3c2d-747c-b3f6-fec905280f85" xlink:to="loc_us-gaap_DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsLiabilityAtFairValue_019ebe77-3c2d-7e39-b10b-254a5833c6fb" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsInHedgesAtFairValueNetAbstract_019ebe77-3c2d-7842-821c-97bb75788fbb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentsInHedgesAtFairValueNetAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_019ebe77-3c2d-7f01-b443-a5d6392fd47a" xlink:to="loc_us-gaap_DerivativeInstrumentsInHedgesAtFairValueNetAbstract_019ebe77-3c2d-7842-821c-97bb75788fbb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsInHedgesAssetsAtFairValue_019ebe77-3c2d-7c3a-b41a-4c9ccafbf326" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentsInHedgesAssetsAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsInHedgesAtFairValueNetAbstract_019ebe77-3c2d-7842-821c-97bb75788fbb" xlink:to="loc_us-gaap_DerivativeInstrumentsInHedgesAssetsAtFairValue_019ebe77-3c2d-7c3a-b41a-4c9ccafbf326" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsInHedgesLiabilitiesAtFairValue_019ebe77-3c2d-7eb7-9715-015d19abe062" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentsInHedgesLiabilitiesAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsInHedgesAtFairValueNetAbstract_019ebe77-3c2d-7842-821c-97bb75788fbb" xlink:to="loc_us-gaap_DerivativeInstrumentsInHedgesLiabilitiesAtFairValue_019ebe77-3c2d-7eb7-9715-015d19abe062" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeFairValueOfDerivativeAsset_019ebe77-3c2d-7bd8-a0c9-d58e8aa948ff" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeFairValueOfDerivativeAsset"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_019ebe77-3c2d-7f01-b443-a5d6392fd47a" xlink:to="loc_us-gaap_DerivativeFairValueOfDerivativeAsset_019ebe77-3c2d-7bd8-a0c9-d58e8aa948ff" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeFairValueOfDerivativeLiability_019ebe77-3c2d-76ff-bbeb-bbfd2cd5f885" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeFairValueOfDerivativeLiability"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_019ebe77-3c2d-7f01-b443-a5d6392fd47a" xlink:to="loc_us-gaap_DerivativeFairValueOfDerivativeLiability_019ebe77-3c2d-76ff-bbeb-bbfd2cd5f885" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/PropertyplantandequipmentnetScheduleofPropertyPlantandEquipmentDetails" xlink:type="simple" xlink:href="fn-20260626.xsd#PropertyplantandequipmentnetScheduleofPropertyPlantandEquipmentDetails"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/PropertyplantandequipmentnetScheduleofPropertyPlantandEquipmentDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentLineItems_019ebe77-3c2e-74e6-bba1-907753f13548" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_019ebe77-3c2e-7cca-a2fc-7996f7b64c55" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfPropertyPlantAndEquipmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_019ebe77-3c2e-74e6-bba1-907753f13548" xlink:to="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_019ebe77-3c2e-7cca-a2fc-7996f7b64c55" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_019ebe77-3c2e-7431-a363-d1c2620254ef" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentByTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_019ebe77-3c2e-7cca-a2fc-7996f7b64c55" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_019ebe77-3c2e-7431-a363-d1c2620254ef" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019ebe77-3c2e-7431-a363-d1c2620254ef_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_019ebe77-3c2e-7431-a363-d1c2620254ef" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019ebe77-3c2e-7431-a363-d1c2620254ef_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019ebe77-3c2e-7be9-9299-0018fefe721b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_019ebe77-3c2e-7431-a363-d1c2620254ef" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019ebe77-3c2e-7be9-9299-0018fefe721b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LandAndLandImprovementsMember_019ebe77-3c2e-7ad8-b32a-b0d383788f48" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LandAndLandImprovementsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019ebe77-3c2e-7be9-9299-0018fefe721b" xlink:to="loc_us-gaap_LandAndLandImprovementsMember_019ebe77-3c2e-7ad8-b32a-b0d383788f48" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BuildingAndBuildingImprovementsMember_019ebe77-3c2e-7412-bd02-56b4a90e60c4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BuildingAndBuildingImprovementsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019ebe77-3c2e-7be9-9299-0018fefe721b" xlink:to="loc_us-gaap_BuildingAndBuildingImprovementsMember_019ebe77-3c2e-7412-bd02-56b4a90e60c4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquipmentMember_019ebe77-3c2e-71db-ac77-e26730cfe947" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquipmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019ebe77-3c2e-7be9-9299-0018fefe721b" xlink:to="loc_us-gaap_EquipmentMember_019ebe77-3c2e-71db-ac77-e26730cfe947" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OfficeEquipmentMember_019ebe77-3c2e-7e5b-8d98-25c992d98df1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OfficeEquipmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019ebe77-3c2e-7be9-9299-0018fefe721b" xlink:to="loc_us-gaap_OfficeEquipmentMember_019ebe77-3c2e-7e5b-8d98-25c992d98df1" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VehiclesMember_019ebe77-3c2e-7f23-a3bc-0dfaab052bb5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VehiclesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019ebe77-3c2e-7be9-9299-0018fefe721b" xlink:to="loc_us-gaap_VehiclesMember_019ebe77-3c2e-7f23-a3bc-0dfaab052bb5" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComputerEquipmentMember_019ebe77-3c2e-7a9a-bc91-ce1b259b35ad" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ComputerEquipmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019ebe77-3c2e-7be9-9299-0018fefe721b" xlink:to="loc_us-gaap_ComputerEquipmentMember_019ebe77-3c2e-7a9a-bc91-ce1b259b35ad" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCapitalizedPropertyPlantAndEquipmentMember_019ebe77-3c2e-782f-b5a5-befa542860c4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherCapitalizedPropertyPlantAndEquipmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019ebe77-3c2e-7be9-9299-0018fefe721b" xlink:to="loc_us-gaap_OtherCapitalizedPropertyPlantAndEquipmentMember_019ebe77-3c2e-782f-b5a5-befa542860c4" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentGross_019ebe77-3c2e-7111-a3fa-fa2be032e8a2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_019ebe77-3c2e-74e6-bba1-907753f13548" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentGross_019ebe77-3c2e-7111-a3fa-fa2be032e8a2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_019ebe77-3c2e-70a1-865e-cf0e00f2ad0a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_019ebe77-3c2e-74e6-bba1-907753f13548" xlink:to="loc_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_019ebe77-3c2e-70a1-865e-cf0e00f2ad0a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_AccumulatedImpairmentReserveOfPropertyPlantAndEquipment_019ebe77-3c2e-754d-aa02-29d47b936e19" xlink:href="fn-20260626.xsd#fn_AccumulatedImpairmentReserveOfPropertyPlantAndEquipment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_019ebe77-3c2e-74e6-bba1-907753f13548" xlink:to="loc_fn_AccumulatedImpairmentReserveOfPropertyPlantAndEquipment_019ebe77-3c2e-754d-aa02-29d47b936e19" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentNet_019ebe77-3c2e-73c9-aef3-6fe5f1aff9bb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_019ebe77-3c2e-74e6-bba1-907753f13548" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentNet_019ebe77-3c2e-73c9-aef3-6fe5f1aff9bb" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/PropertyplantandequipmentnetAdditionalInformationDetails" xlink:type="simple" xlink:href="fn-20260626.xsd#PropertyplantandequipmentnetAdditionalInformationDetails"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/PropertyplantandequipmentnetAdditionalInformationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentLineItems_019ebe77-3c2e-705d-b86e-7ae0f311f7dc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_019ebe77-3c2e-70e8-935f-d4dcc980e1fe" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfPropertyPlantAndEquipmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_019ebe77-3c2e-705d-b86e-7ae0f311f7dc" xlink:to="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_019ebe77-3c2e-70e8-935f-d4dcc980e1fe" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByAssetClassAxis_019ebe77-3c2e-764f-a8d2-a1a351d9b7fc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByAssetClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_019ebe77-3c2e-70e8-935f-d4dcc980e1fe" xlink:to="loc_us-gaap_FairValueByAssetClassAxis_019ebe77-3c2e-764f-a8d2-a1a351d9b7fc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_019ebe77-3c2e-764f-a8d2-a1a351d9b7fc_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByAssetClassAxis_019ebe77-3c2e-764f-a8d2-a1a351d9b7fc" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_019ebe77-3c2e-764f-a8d2-a1a351d9b7fc_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_019ebe77-3c2e-7656-a232-85dac300bbea" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByAssetClassAxis_019ebe77-3c2e-764f-a8d2-a1a351d9b7fc" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_019ebe77-3c2e-7656-a232-85dac300bbea" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentMember_019ebe77-3c2e-7c43-9723-321c3f4fc565" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_019ebe77-3c2e-7656-a232-85dac300bbea" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentMember_019ebe77-3c2e-7c43-9723-321c3f4fc565" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Depreciation_019ebe77-3c2e-70c7-8e0e-6cae10c0975c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Depreciation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_019ebe77-3c2e-705d-b86e-7ae0f311f7dc" xlink:to="loc_us-gaap_Depreciation_019ebe77-3c2e-70c7-8e0e-6cae10c0975c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentDisposals_019ebe77-3c2e-7e6e-bb0e-4972fa060493" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentDisposals"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_019ebe77-3c2e-705d-b86e-7ae0f311f7dc" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentDisposals_019ebe77-3c2e-7e6e-bb0e-4972fa060493" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_AccumulatedImpairmentReserveOfPropertyPlantAndEquipment_019ebe77-3c2e-7acf-b699-83c375a24283" xlink:href="fn-20260626.xsd#fn_AccumulatedImpairmentReserveOfPropertyPlantAndEquipment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_019ebe77-3c2e-705d-b86e-7ae0f311f7dc" xlink:to="loc_fn_AccumulatedImpairmentReserveOfPropertyPlantAndEquipment_019ebe77-3c2e-7acf-b699-83c375a24283" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/IntangiblesScheduleofIntangibleAssetsDetails" xlink:type="simple" xlink:href="fn-20260626.xsd#IntangiblesScheduleofIntangibleAssetsDetails"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/IntangiblesScheduleofIntangibleAssetsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_019ec9cd-22a7-784e-b400-c5fe1831bfae" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_019ec9cd-22a7-7811-8e2c-1b9d15c34318" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_019ec9cd-22a7-784e-b400-c5fe1831bfae" xlink:to="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_019ec9cd-22a7-7811-8e2c-1b9d15c34318" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_019ec9cd-22a7-70e9-ae36-d0af2466e9ed" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_019ec9cd-22a7-7811-8e2c-1b9d15c34318" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_019ec9cd-22a7-70e9-ae36-d0af2466e9ed" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019ec9cd-22a7-70e9-ae36-d0af2466e9ed_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_019ec9cd-22a7-70e9-ae36-d0af2466e9ed" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019ec9cd-22a7-70e9-ae36-d0af2466e9ed_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019ec9cd-22a7-7c40-abf3-b4ece6f8f152" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_019ec9cd-22a7-70e9-ae36-d0af2466e9ed" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019ec9cd-22a7-7c40-abf3-b4ece6f8f152" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SoftwareAndSoftwareDevelopmentCostsMember_019ec9cd-22a7-77fc-9d72-0ff06d9de4e4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SoftwareAndSoftwareDevelopmentCostsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019ec9cd-22a7-7c40-abf3-b4ece6f8f152" xlink:to="loc_us-gaap_SoftwareAndSoftwareDevelopmentCostsMember_019ec9cd-22a7-77fc-9d72-0ff06d9de4e4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsGross_019ec9cd-22a7-7cf1-84e5-666e7237887e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_019ec9cd-22a7-784e-b400-c5fe1831bfae" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsGross_019ec9cd-22a7-7cf1-84e5-666e7237887e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_019ec9cd-22a7-72fb-b8a5-f64ea44563d9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_019ec9cd-22a7-784e-b400-c5fe1831bfae" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_019ec9cd-22a7-72fb-b8a5-f64ea44563d9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsNet_019ec9cd-22a7-792a-b505-ca548ebaad41" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_019ec9cd-22a7-784e-b400-c5fe1831bfae" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsNet_019ec9cd-22a7-792a-b505-ca548ebaad41" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/IntangiblesScheduleofWeightedAverageRemainingLifeofIntangibleAssetsDetails" xlink:type="simple" xlink:href="fn-20260626.xsd#IntangiblesScheduleofWeightedAverageRemainingLifeofIntangibleAssetsDetails"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/IntangiblesScheduleofWeightedAverageRemainingLifeofIntangibleAssetsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_fn_FiniteLivedIntangibleLiabilitiesLineItems_019ebe77-3c2e-71f1-8fc1-d7fd352d4214" xlink:href="fn-20260626.xsd#fn_FiniteLivedIntangibleLiabilitiesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_019ebe77-3c2e-7955-b01a-15fa77d1f23d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_fn_FiniteLivedIntangibleLiabilitiesLineItems_019ebe77-3c2e-71f1-8fc1-d7fd352d4214" xlink:to="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_019ebe77-3c2e-7955-b01a-15fa77d1f23d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_019ebe77-3c2e-708f-a96b-95d9215478d2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_019ebe77-3c2e-7955-b01a-15fa77d1f23d" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_019ebe77-3c2e-708f-a96b-95d9215478d2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019ebe77-3c2e-708f-a96b-95d9215478d2_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_019ebe77-3c2e-708f-a96b-95d9215478d2" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019ebe77-3c2e-708f-a96b-95d9215478d2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019ebe77-3c2e-73be-8dfd-3e38852f7459" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_019ebe77-3c2e-708f-a96b-95d9215478d2" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019ebe77-3c2e-73be-8dfd-3e38852f7459" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SoftwareAndSoftwareDevelopmentCostsMember_019ec9cc-9b65-7e31-8cb4-af06e9197fb5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SoftwareAndSoftwareDevelopmentCostsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019ebe77-3c2e-73be-8dfd-3e38852f7459" xlink:to="loc_us-gaap_SoftwareAndSoftwareDevelopmentCostsMember_019ec9cc-9b65-7e31-8cb4-af06e9197fb5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetUsefulLife_019ec9cb-ef6b-7780-85a9-a05f393bc59b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetUsefulLife"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_FiniteLivedIntangibleLiabilitiesLineItems_019ebe77-3c2e-71f1-8fc1-d7fd352d4214" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetUsefulLife_019ec9cb-ef6b-7780-85a9-a05f393bc59b" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/SeveranceliabilitiesScheduleofPrincipalWeightedAverageActuarialAssumptionsUsedtoDetermineSeveranceLiabilitiesDetails" xlink:type="simple" xlink:href="fn-20260626.xsd#SeveranceliabilitiesScheduleofPrincipalWeightedAverageActuarialAssumptionsUsedtoDetermineSeveranceLiabilitiesDetails"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/SeveranceliabilitiesScheduleofPrincipalWeightedAverageActuarialAssumptionsUsedtoDetermineSeveranceLiabilitiesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_019ebe77-3cfe-763b-8722-093c17f9d8fb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable_019ebe77-3cfe-71ef-aa76-db6ccb8dca6b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_019ebe77-3cfe-763b-8722-093c17f9d8fb" xlink:to="loc_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable_019ebe77-3cfe-71ef-aa76-db6ccb8dca6b" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_019ebe77-3cfe-7326-b4f2-c8e2348d96f0" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable_019ebe77-3cfe-71ef-aa76-db6ccb8dca6b" xlink:to="loc_srt_RangeAxis_019ebe77-3cfe-7326-b4f2-c8e2348d96f0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019ebe77-3cfe-7326-b4f2-c8e2348d96f0_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_019ebe77-3cfe-7326-b4f2-c8e2348d96f0" xlink:to="loc_srt_RangeMember_019ebe77-3cfe-7326-b4f2-c8e2348d96f0_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019ebe77-3cfe-7a9e-8e64-342704c3c0c9" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_019ebe77-3cfe-7326-b4f2-c8e2348d96f0" xlink:to="loc_srt_RangeMember_019ebe77-3cfe-7a9e-8e64-342704c3c0c9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_019ebe77-3cfe-7f4c-86ce-d1d873f77c5f" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019ebe77-3cfe-7a9e-8e64-342704c3c0c9" xlink:to="loc_srt_MinimumMember_019ebe77-3cfe-7f4c-86ce-d1d873f77c5f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_019ebe77-3cfe-7c26-90f1-9c0f4560da95" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019ebe77-3cfe-7a9e-8e64-342704c3c0c9" xlink:to="loc_srt_MaximumMember_019ebe77-3cfe-7c26-90f1-9c0f4560da95" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate_019ebe77-3cfe-778e-9080-662931c6be9c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ebe77-3cfe-763b-8722-093c17f9d8fb" xlink:to="loc_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate_019ebe77-3cfe-778e-9080-662931c6be9c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease_019ebe77-3cfe-71c3-ad69-cf06f94a27e1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ebe77-3cfe-763b-8722-093c17f9d8fb" xlink:to="loc_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease_019ebe77-3cfe-71c3-ad69-cf06f94a27e1" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/SharebasedcompensationScheduleofShareBasedCompensationExpenseRecordedinCondensedConsolidatedStatementsofOperationsandComprehensiveIncomeDetails" xlink:type="simple" xlink:href="fn-20260626.xsd#SharebasedcompensationScheduleofShareBasedCompensationExpenseRecordedinCondensedConsolidatedStatementsofOperationsandComprehensiveIncomeDetails"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/SharebasedcompensationScheduleofShareBasedCompensationExpenseRecordedinCondensedConsolidatedStatementsofOperationsandComprehensiveIncomeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_019ebe77-3cfe-7367-9436-4c8a062a790e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_019ebe77-3cfe-767e-8f00-c9748dc5e80c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_019ebe77-3cfe-7367-9436-4c8a062a790e" xlink:to="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_019ebe77-3cfe-767e-8f00-c9748dc5e80c" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementOfIncomeLocationBalanceAxis_019ebe77-3cfe-78ce-8fcc-2dc7cb0a918f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementOfIncomeLocationBalanceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_019ebe77-3cfe-767e-8f00-c9748dc5e80c" xlink:to="loc_us-gaap_StatementOfIncomeLocationBalanceAxis_019ebe77-3cfe-78ce-8fcc-2dc7cb0a918f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensation_019ebe77-3cfe-715e-b654-9a13e520d273" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_019ebe77-3cfe-7367-9436-4c8a062a790e" xlink:to="loc_us-gaap_ShareBasedCompensation_019ebe77-3cfe-715e-b654-9a13e520d273" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/SharebasedcompensationScheduleofShareBasedCompensationExpenseRecordedinCondensedConsolidatedStatementsofOperationsandComprehensiveIncomeDetails_1" xlink:type="simple" xlink:href="fn-20260626.xsd#SharebasedcompensationScheduleofShareBasedCompensationExpenseRecordedinCondensedConsolidatedStatementsofOperationsandComprehensiveIncomeDetails_1"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/SharebasedcompensationScheduleofShareBasedCompensationExpenseRecordedinCondensedConsolidatedStatementsofOperationsandComprehensiveIncomeDetails_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_019ebe77-3cfe-7367-9436-4c8a062a790e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_019ebe77-3cfe-767e-8f00-c9748dc5e80c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_019ebe77-3cfe-7367-9436-4c8a062a790e" xlink:to="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_019ebe77-3cfe-767e-8f00-c9748dc5e80c" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensation_019ebe77-3cfe-715e-b654-9a13e520d273" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_019ebe77-3cfe-7367-9436-4c8a062a790e" xlink:to="loc_us-gaap_ShareBasedCompensation_019ebe77-3cfe-715e-b654-9a13e520d273" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/SharebasedcompensationAdditionalInformationDetails" xlink:type="simple" xlink:href="fn-20260626.xsd#SharebasedcompensationAdditionalInformationDetails"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/SharebasedcompensationAdditionalInformationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-732d-a999-2af24978469c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019ebe77-3cfe-71cb-9430-a085d9f57d17" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-732d-a999-2af24978469c" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019ebe77-3cfe-71cb-9430-a085d9f57d17" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameAxis_019ebe77-3cfe-7e4d-8b91-94a2eb987197" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PlanNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019ebe77-3cfe-71cb-9430-a085d9f57d17" xlink:to="loc_us-gaap_PlanNameAxis_019ebe77-3cfe-7e4d-8b91-94a2eb987197" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameDomain_019ebe77-3cfe-7e4d-8b91-94a2eb987197_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PlanNameAxis_019ebe77-3cfe-7e4d-8b91-94a2eb987197" xlink:to="loc_us-gaap_PlanNameDomain_019ebe77-3cfe-7e4d-8b91-94a2eb987197_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameDomain_019ebe77-3cfe-7a8d-9670-eb083068b9a8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PlanNameAxis_019ebe77-3cfe-7e4d-8b91-94a2eb987197" xlink:to="loc_us-gaap_PlanNameDomain_019ebe77-3cfe-7a8d-9670-eb083068b9a8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_EquityIncentivePlansMember_019ebe77-3cfe-7f5d-9dcd-81fdd0ca4987" xlink:href="fn-20260626.xsd#fn_EquityIncentivePlansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PlanNameDomain_019ebe77-3cfe-7a8d-9670-eb083068b9a8" xlink:to="loc_fn_EquityIncentivePlansMember_019ebe77-3cfe-7f5d-9dcd-81fdd0ca4987" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_EquityIncentivePlans2020Member_019ebe77-3cfe-7e69-aa50-df64d043cf53" xlink:href="fn-20260626.xsd#fn_EquityIncentivePlans2020Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_EquityIncentivePlansMember_019ebe77-3cfe-7f5d-9dcd-81fdd0ca4987" xlink:to="loc_fn_EquityIncentivePlans2020Member_019ebe77-3cfe-7e69-aa50-df64d043cf53" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_InducementEquityIncentivePlan2017Member_019ebe77-3cfe-7c8f-bdcf-ae574dd81da3" xlink:href="fn-20260626.xsd#fn_InducementEquityIncentivePlan2017Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_EquityIncentivePlansMember_019ebe77-3cfe-7f5d-9dcd-81fdd0ca4987" xlink:to="loc_fn_InducementEquityIncentivePlan2017Member_019ebe77-3cfe-7c8f-bdcf-ae574dd81da3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_019ebe77-3cfe-74e8-9d2c-5aeb8fcdcdae" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019ebe77-3cfe-71cb-9430-a085d9f57d17" xlink:to="loc_us-gaap_AwardTypeAxis_019ebe77-3cfe-74e8-9d2c-5aeb8fcdcdae" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019ebe77-3cfe-74e8-9d2c-5aeb8fcdcdae_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_019ebe77-3cfe-74e8-9d2c-5aeb8fcdcdae" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019ebe77-3cfe-74e8-9d2c-5aeb8fcdcdae_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019ebe77-3cfe-7bf6-a755-b84619997d21" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_019ebe77-3cfe-74e8-9d2c-5aeb8fcdcdae" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019ebe77-3cfe-7bf6-a755-b84619997d21" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_RestrictedStockUnitsRSUAndPerformanceShareMember_019ebe77-3cfe-72e2-9c00-51524c1dfdf8" xlink:href="fn-20260626.xsd#fn_RestrictedStockUnitsRSUAndPerformanceShareMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019ebe77-3cfe-7bf6-a755-b84619997d21" xlink:to="loc_fn_RestrictedStockUnitsRSUAndPerformanceShareMember_019ebe77-3cfe-72e2-9c00-51524c1dfdf8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_019ebe77-3cfe-7f8e-9c07-4f0fb4fc6dc3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestrictedStockUnitsRSUMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_RestrictedStockUnitsRSUAndPerformanceShareMember_019ebe77-3cfe-72e2-9c00-51524c1dfdf8" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_019ebe77-3cfe-7f8e-9c07-4f0fb4fc6dc3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PerformanceSharesMember_019ebe77-3cfe-7067-aa5d-6268db918e66" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PerformanceSharesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_RestrictedStockUnitsRSUAndPerformanceShareMember_019ebe77-3cfe-72e2-9c00-51524c1dfdf8" xlink:to="loc_us-gaap_PerformanceSharesMember_019ebe77-3cfe-7067-aa5d-6268db918e66" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VestingAxis_019ebe77-3cfe-7979-bf8f-3ccfb7f8a445" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VestingAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019ebe77-3cfe-71cb-9430-a085d9f57d17" xlink:to="loc_us-gaap_VestingAxis_019ebe77-3cfe-7979-bf8f-3ccfb7f8a445" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VestingDomain_019ebe77-3cfe-7979-bf8f-3ccfb7f8a445_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VestingDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_VestingAxis_019ebe77-3cfe-7979-bf8f-3ccfb7f8a445" xlink:to="loc_us-gaap_VestingDomain_019ebe77-3cfe-7979-bf8f-3ccfb7f8a445_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VestingDomain_019ebe77-3cfe-7f40-a30d-20cf73688f72" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VestingDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_VestingAxis_019ebe77-3cfe-7979-bf8f-3ccfb7f8a445" xlink:to="loc_us-gaap_VestingDomain_019ebe77-3cfe-7f40-a30d-20cf73688f72" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_VestingOptionOneMember_019ebe77-3cfe-7502-9caf-a332d0ebc4fe" xlink:href="fn-20260626.xsd#fn_VestingOptionOneMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VestingDomain_019ebe77-3cfe-7f40-a30d-20cf73688f72" xlink:to="loc_fn_VestingOptionOneMember_019ebe77-3cfe-7502-9caf-a332d0ebc4fe" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_VestingOptionTwoMember_019ebe77-3cfe-70ab-bd30-bf21bfc3b6f4" xlink:href="fn-20260626.xsd#fn_VestingOptionTwoMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VestingDomain_019ebe77-3cfe-7f40-a30d-20cf73688f72" xlink:to="loc_fn_VestingOptionTwoMember_019ebe77-3cfe-70ab-bd30-bf21bfc3b6f4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_PeriodTenMember_019ebe77-3cfe-7b43-9aa2-9f53fd0dc3c4" xlink:href="fn-20260626.xsd#fn_PeriodTenMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VestingDomain_019ebe77-3cfe-7f40-a30d-20cf73688f72" xlink:to="loc_fn_PeriodTenMember_019ebe77-3cfe-7b43-9aa2-9f53fd0dc3c4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_PeriodSixMember_019ebe77-3cfe-71b4-aa75-1cfe1ff883ae" xlink:href="fn-20260626.xsd#fn_PeriodSixMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VestingDomain_019ebe77-3cfe-7f40-a30d-20cf73688f72" xlink:to="loc_fn_PeriodSixMember_019ebe77-3cfe-71b4-aa75-1cfe1ff883ae" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_TitleOfIndividualAxis_019ebe77-3cfe-7e04-a020-487453fb322e" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_TitleOfIndividualAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019ebe77-3cfe-71cb-9430-a085d9f57d17" xlink:to="loc_srt_TitleOfIndividualAxis_019ebe77-3cfe-7e04-a020-487453fb322e" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_TitleOfIndividualWithRelationshipToEntityDomain_019ebe77-3cfe-7e04-a020-487453fb322e_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_TitleOfIndividualWithRelationshipToEntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_TitleOfIndividualAxis_019ebe77-3cfe-7e04-a020-487453fb322e" xlink:to="loc_srt_TitleOfIndividualWithRelationshipToEntityDomain_019ebe77-3cfe-7e04-a020-487453fb322e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_TitleOfIndividualWithRelationshipToEntityDomain_019ebe77-3cfe-7fe8-bf08-b1067d16e646" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_TitleOfIndividualWithRelationshipToEntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_TitleOfIndividualAxis_019ebe77-3cfe-7e04-a020-487453fb322e" xlink:to="loc_srt_TitleOfIndividualWithRelationshipToEntityDomain_019ebe77-3cfe-7fe8-bf08-b1067d16e646" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_NonEmployeeDirectorMember_019ebe77-3cfe-77a4-b0c8-a57114d3166a" xlink:href="fn-20260626.xsd#fn_NonEmployeeDirectorMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_TitleOfIndividualWithRelationshipToEntityDomain_019ebe77-3cfe-7fe8-bf08-b1067d16e646" xlink:to="loc_fn_NonEmployeeDirectorMember_019ebe77-3cfe-77a4-b0c8-a57114d3166a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_ExecutiveDirectorMember_019ebe77-3cfe-7b00-b309-90069032f889" xlink:href="fn-20260626.xsd#fn_ExecutiveDirectorMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_TitleOfIndividualWithRelationshipToEntityDomain_019ebe77-3cfe-7fe8-bf08-b1067d16e646" xlink:to="loc_fn_ExecutiveDirectorMember_019ebe77-3cfe-7b00-b309-90069032f889" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_019ebe77-3cfe-7797-9509-973916a3f470" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019ebe77-3cfe-71cb-9430-a085d9f57d17" xlink:to="loc_srt_RangeAxis_019ebe77-3cfe-7797-9509-973916a3f470" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019ebe77-3cfe-7797-9509-973916a3f470_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_019ebe77-3cfe-7797-9509-973916a3f470" xlink:to="loc_srt_RangeMember_019ebe77-3cfe-7797-9509-973916a3f470_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019ebe77-3cfe-73c9-b9a1-b2da23f9ad3d" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_019ebe77-3cfe-7797-9509-973916a3f470" xlink:to="loc_srt_RangeMember_019ebe77-3cfe-73c9-b9a1-b2da23f9ad3d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_019ebe77-3cfe-71c9-bb60-14a70156b196" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019ebe77-3cfe-73c9-b9a1-b2da23f9ad3d" xlink:to="loc_srt_MinimumMember_019ebe77-3cfe-71c9-bb60-14a70156b196" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_019ebe77-3cfe-7c5a-ab6d-cba1b9338a9c" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019ebe77-3cfe-73c9-b9a1-b2da23f9ad3d" xlink:to="loc_srt_MaximumMember_019ebe77-3cfe-7c5a-ab6d-cba1b9338a9c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount_019ebe77-3cfe-7de6-a5c2-c3221219853a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-732d-a999-2af24978469c" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount_019ebe77-3cfe-7de6-a5c2-c3221219853a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_019ebe77-3cfe-702f-8cb9-8a6d725943ec" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-732d-a999-2af24978469c" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_019ebe77-3cfe-702f-8cb9-8a6d725943ec" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_019ebe77-3cfe-7375-9370-cd8fec9072f8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockCapitalSharesReservedForFutureIssuance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-732d-a999-2af24978469c" xlink:to="loc_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_019ebe77-3cfe-7375-9370-cd8fec9072f8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized_019ebe77-3cfe-7e88-9497-fb6d05dad66a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-732d-a999-2af24978469c" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized_019ebe77-3cfe-7e88-9497-fb6d05dad66a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_019ebe77-3cfe-7278-84a1-9ff789e2cd38" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-732d-a999-2af24978469c" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_019ebe77-3cfe-7278-84a1-9ff789e2cd38" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage_019ebe77-3cfe-7631-891f-12be5998333f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-732d-a999-2af24978469c" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage_019ebe77-3cfe-7631-891f-12be5998333f" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedInPeriodGrantDateFairValue_019ebe77-3cfe-7d6c-8977-af64a8a71723" xlink:href="fn-20260626.xsd#fn_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedInPeriodGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-732d-a999-2af24978469c" xlink:to="loc_fn_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedInPeriodGrantDateFairValue_019ebe77-3cfe-7d6c-8977-af64a8a71723" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueOutstanding_019ebe77-3cfe-7073-9f12-6a6ff49a67b8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-732d-a999-2af24978469c" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueOutstanding_019ebe77-3cfe-7073-9f12-6a6ff49a67b8" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_019ebe77-3cfe-78d4-bd1c-6c30eaf913d4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-732d-a999-2af24978469c" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_019ebe77-3cfe-78d4-bd1c-6c30eaf913d4" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_019ebe77-3cfe-7a7a-bc26-e14203a953e5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-732d-a999-2af24978469c" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_019ebe77-3cfe-7a7a-bc26-e14203a953e5" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharesPaidForTaxWithholdingForShareBasedCompensation_019ebe77-3cfe-7f96-932a-d54b1f0af61e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SharesPaidForTaxWithholdingForShareBasedCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-732d-a999-2af24978469c" xlink:to="loc_us-gaap_SharesPaidForTaxWithholdingForShareBasedCompensation_019ebe77-3cfe-7f96-932a-d54b1f0af61e" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation_019ebe77-3cfe-70fa-9bcb-28a16cdfcfa8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-732d-a999-2af24978469c" xlink:to="loc_us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation_019ebe77-3cfe-70fa-9bcb-28a16cdfcfa8" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights_019ebe77-3cfe-7815-8bff-dee2bfeea704" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-732d-a999-2af24978469c" xlink:to="loc_us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights_019ebe77-3cfe-7815-8bff-dee2bfeea704" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_019ebe77-3cfe-7b6d-81d7-06f3808d82ec" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-732d-a999-2af24978469c" xlink:to="loc_us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_019ebe77-3cfe-7b6d-81d7-06f3808d82ec" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_ClassOfWarrantOrRightWarrantsVested_019ebe77-3cfe-77da-80c4-6493ba298e12" xlink:href="fn-20260626.xsd#fn_ClassOfWarrantOrRightWarrantsVested"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-732d-a999-2af24978469c" xlink:to="loc_fn_ClassOfWarrantOrRightWarrantsVested_019ebe77-3cfe-77da-80c4-6493ba298e12" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_ClassOfWarrantOrRightGrantDateFairValuePerShare_019ebe77-3cfe-7052-a9c8-1c8492a2c971" xlink:href="fn-20260626.xsd#fn_ClassOfWarrantOrRightGrantDateFairValuePerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-732d-a999-2af24978469c" xlink:to="loc_fn_ClassOfWarrantOrRightGrantDateFairValuePerShare_019ebe77-3cfe-7052-a9c8-1c8492a2c971" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_ClassOfWarrantOrRightGrantDateFairValue_019ebe77-3cfe-721e-98df-e4d1ba09b001" xlink:href="fn-20260626.xsd#fn_ClassOfWarrantOrRightGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-732d-a999-2af24978469c" xlink:to="loc_fn_ClassOfWarrantOrRightGrantDateFairValue_019ebe77-3cfe-721e-98df-e4d1ba09b001" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfWarrantOrRightOutstanding_019f6641-2055-7992-ab57-8fd045e3e3ea" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfWarrantOrRightOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-732d-a999-2af24978469c" xlink:to="loc_us-gaap_ClassOfWarrantOrRightOutstanding_019f6641-2055-7992-ab57-8fd045e3e3ea" xlink:type="arc" order="17"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/SharebasedcompensationSharebasedawardactivityDetails" xlink:type="simple" xlink:href="fn-20260626.xsd#SharebasedcompensationSharebasedawardactivityDetails"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/SharebasedcompensationSharebasedawardactivityDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-7862-b55e-35d8d026a1ed" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019ebe77-3cfe-7811-85ab-234203e3a011" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-7862-b55e-35d8d026a1ed" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019ebe77-3cfe-7811-85ab-234203e3a011" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_019ebe77-3cfe-78f2-ab81-2d5122e9dec9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019ebe77-3cfe-7811-85ab-234203e3a011" xlink:to="loc_us-gaap_AwardTypeAxis_019ebe77-3cfe-78f2-ab81-2d5122e9dec9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019ebe77-3cfe-78f2-ab81-2d5122e9dec9_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_019ebe77-3cfe-78f2-ab81-2d5122e9dec9" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019ebe77-3cfe-78f2-ab81-2d5122e9dec9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019ebe77-3cfe-7284-bb1d-e1060f6c1a44" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_019ebe77-3cfe-78f2-ab81-2d5122e9dec9" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019ebe77-3cfe-7284-bb1d-e1060f6c1a44" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_019ebe77-3cfe-7c70-befe-86b7ad2bfa65" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestrictedStockUnitsRSUMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019ebe77-3cfe-7284-bb1d-e1060f6c1a44" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_019ebe77-3cfe-7c70-befe-86b7ad2bfa65" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PerformanceSharesMember_019ebe77-3cfe-7f64-877f-01379497c9aa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PerformanceSharesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019ebe77-3cfe-7284-bb1d-e1060f6c1a44" xlink:to="loc_us-gaap_PerformanceSharesMember_019ebe77-3cfe-7f64-877f-01379497c9aa" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameAxis_019ebe77-3cfe-7eba-a7aa-7c266fe8812b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PlanNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019ebe77-3cfe-7811-85ab-234203e3a011" xlink:to="loc_us-gaap_PlanNameAxis_019ebe77-3cfe-7eba-a7aa-7c266fe8812b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameDomain_019ebe77-3cfe-7eba-a7aa-7c266fe8812b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PlanNameAxis_019ebe77-3cfe-7eba-a7aa-7c266fe8812b" xlink:to="loc_us-gaap_PlanNameDomain_019ebe77-3cfe-7eba-a7aa-7c266fe8812b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameDomain_019ebe77-3cfe-75bc-bd65-4f4f38219e7b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PlanNameAxis_019ebe77-3cfe-7eba-a7aa-7c266fe8812b" xlink:to="loc_us-gaap_PlanNameDomain_019ebe77-3cfe-75bc-bd65-4f4f38219e7b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_EquityIncentivePlans2020Member_019ebe77-3cfe-7d0e-a822-f104af107fc9" xlink:href="fn-20260626.xsd#fn_EquityIncentivePlans2020Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PlanNameDomain_019ebe77-3cfe-75bc-bd65-4f4f38219e7b" xlink:to="loc_fn_EquityIncentivePlans2020Member_019ebe77-3cfe-7d0e-a822-f104af107fc9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_InducementEquityIncentivePlan2017Member_019ebe77-3cfe-735e-8b3f-c6a66f206ae4" xlink:href="fn-20260626.xsd#fn_InducementEquityIncentivePlan2017Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PlanNameDomain_019ebe77-3cfe-75bc-bd65-4f4f38219e7b" xlink:to="loc_fn_InducementEquityIncentivePlan2017Member_019ebe77-3cfe-735e-8b3f-c6a66f206ae4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_019ebe77-3cfe-7998-8077-ade1d03f98cb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-7862-b55e-35d8d026a1ed" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_019ebe77-3cfe-7998-8077-ade1d03f98cb" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_019ebe77-3cfe-7d64-b434-87a51e9431bc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-7862-b55e-35d8d026a1ed" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_019ebe77-3cfe-7d64-b434-87a51e9431bc" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/SharebasedcompensationScheduleofRestrictedShareUnitActivityDetails" xlink:type="simple" xlink:href="fn-20260626.xsd#SharebasedcompensationScheduleofRestrictedShareUnitActivityDetails"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/SharebasedcompensationScheduleofRestrictedShareUnitActivityDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-7b7f-9ceb-d2e1fe9a9b68" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019ebe77-3cfe-77e3-9553-6399b478134a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-7b7f-9ceb-d2e1fe9a9b68" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019ebe77-3cfe-77e3-9553-6399b478134a" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_019ebe77-3cfe-7ee4-b7b8-33504acd41cf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019ebe77-3cfe-77e3-9553-6399b478134a" xlink:to="loc_us-gaap_AwardTypeAxis_019ebe77-3cfe-7ee4-b7b8-33504acd41cf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019ebe77-3cfe-7ee4-b7b8-33504acd41cf_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_019ebe77-3cfe-7ee4-b7b8-33504acd41cf" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019ebe77-3cfe-7ee4-b7b8-33504acd41cf_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019ebe77-3cfe-7e9e-99b3-a0b839274b21" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_019ebe77-3cfe-7ee4-b7b8-33504acd41cf" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019ebe77-3cfe-7e9e-99b3-a0b839274b21" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_019ebe77-3cfe-73d0-aaa3-f48572a5c49a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestrictedStockUnitsRSUMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019ebe77-3cfe-7e9e-99b3-a0b839274b21" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_019ebe77-3cfe-73d0-aaa3-f48572a5c49a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_019ebe77-3cfe-72c1-b099-6e16b9d29b68" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-7b7f-9ceb-d2e1fe9a9b68" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_019ebe77-3cfe-72c1-b099-6e16b9d29b68" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_019ebe77-3cfe-75c9-bbe8-d418d7f933ee" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_019ebe77-3cfe-72c1-b099-6e16b9d29b68" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_019ebe77-3cfe-75c9-bbe8-d418d7f933ee" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_019ebe77-3cfe-7b2f-aa25-fe734a804e28" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_019ebe77-3cfe-72c1-b099-6e16b9d29b68" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_019ebe77-3cfe-7b2f-aa25-fe734a804e28" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_019ebe77-3cfe-75b9-a17c-846ad986c8c2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_019ebe77-3cfe-72c1-b099-6e16b9d29b68" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_019ebe77-3cfe-75b9-a17c-846ad986c8c2" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_019ebe77-3cfe-73ff-ab5d-44679a31963e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_019ebe77-3cfe-72c1-b099-6e16b9d29b68" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_019ebe77-3cfe-73ff-ab5d-44679a31963e" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_019ebe77-3cfe-79c4-a74d-44ca6331016f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpectedToVestNumber_019ebe77-3cfe-7525-9ad7-3671ce5fcf2a" xlink:href="fn-20260626.xsd#fn_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpectedToVestNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-7b7f-9ceb-d2e1fe9a9b68" xlink:to="loc_fn_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpectedToVestNumber_019ebe77-3cfe-7525-9ad7-3671ce5fcf2a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_019ebe77-3cfe-7d11-81ee-81de4fb760f2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-7b7f-9ceb-d2e1fe9a9b68" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_019ebe77-3cfe-7d11-81ee-81de4fb760f2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_019ebe77-3cfe-7159-b405-d0d6ef0f5023" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_019ebe77-3cfe-7d11-81ee-81de4fb760f2" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_019ebe77-3cfe-7159-b405-d0d6ef0f5023" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_019ebe77-3cfe-7e04-b844-f400a68730a7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_019ebe77-3cfe-7d11-81ee-81de4fb760f2" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_019ebe77-3cfe-7e04-b844-f400a68730a7" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_019ebe77-3cfe-7105-b197-333f8f83299a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_019ebe77-3cfe-7d11-81ee-81de4fb760f2" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_019ebe77-3cfe-7105-b197-333f8f83299a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_019ebe77-3cfe-7830-be7b-0bedede90ec0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_019ebe77-3cfe-7d11-81ee-81de4fb760f2" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_019ebe77-3cfe-7830-be7b-0bedede90ec0" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_019ebe77-3cfe-7e16-bb1f-49fb62dcadfa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpectedToVestWeightedAverageGrantDateFairValue_019ebe77-3cfe-7703-ad42-4d9139f6b43b" xlink:href="fn-20260626.xsd#fn_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpectedToVestWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-7b7f-9ceb-d2e1fe9a9b68" xlink:to="loc_fn_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpectedToVestWeightedAverageGrantDateFairValue_019ebe77-3cfe-7703-ad42-4d9139f6b43b" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/SharebasedcompensationScheduleofPerformanceShareUnitActivityDetails" xlink:type="simple" xlink:href="fn-20260626.xsd#SharebasedcompensationScheduleofPerformanceShareUnitActivityDetails"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/SharebasedcompensationScheduleofPerformanceShareUnitActivityDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-7ce3-b6fb-3962a7325382" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019ebe77-3cfe-773a-98d7-7d70d45adab7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-7ce3-b6fb-3962a7325382" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019ebe77-3cfe-773a-98d7-7d70d45adab7" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_019ebe77-3cfe-7082-9746-36a39ddcd8e5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019ebe77-3cfe-773a-98d7-7d70d45adab7" xlink:to="loc_us-gaap_AwardTypeAxis_019ebe77-3cfe-7082-9746-36a39ddcd8e5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019ebe77-3cfe-7082-9746-36a39ddcd8e5_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_019ebe77-3cfe-7082-9746-36a39ddcd8e5" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019ebe77-3cfe-7082-9746-36a39ddcd8e5_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019ebe77-3cfe-7858-ab53-565840863184" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_019ebe77-3cfe-7082-9746-36a39ddcd8e5" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019ebe77-3cfe-7858-ab53-565840863184" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PerformanceSharesMember_019ebe77-3cfe-726a-8b26-eedec671bc10" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PerformanceSharesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019ebe77-3cfe-7858-ab53-565840863184" xlink:to="loc_us-gaap_PerformanceSharesMember_019ebe77-3cfe-726a-8b26-eedec671bc10" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_019ebe77-3cfe-7a74-9de3-997805c3e86d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-7ce3-b6fb-3962a7325382" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_019ebe77-3cfe-7a74-9de3-997805c3e86d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_019ebe77-3cfe-730f-b699-3fc76b802b2d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_019ebe77-3cfe-7a74-9de3-997805c3e86d" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_019ebe77-3cfe-730f-b699-3fc76b802b2d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_019ebe77-3cfe-7988-a609-e38983e7de90" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_019ebe77-3cfe-7a74-9de3-997805c3e86d" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_019ebe77-3cfe-7988-a609-e38983e7de90" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_019ebe77-3cfe-7e76-9e63-422a23454d67" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_019ebe77-3cfe-7a74-9de3-997805c3e86d" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_019ebe77-3cfe-7e76-9e63-422a23454d67" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_019f663f-4c05-73f1-aae7-b2faf474dc2b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_019ebe77-3cfe-7a74-9de3-997805c3e86d" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_019f663f-4c05-73f1-aae7-b2faf474dc2b" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_019ebe77-3cfe-7f6b-8444-4593f76450f8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpectedToVestNumber_019ebe77-3cfe-7f6a-8aa7-df1292b6ebb8" xlink:href="fn-20260626.xsd#fn_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpectedToVestNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-7ce3-b6fb-3962a7325382" xlink:to="loc_fn_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpectedToVestNumber_019ebe77-3cfe-7f6a-8aa7-df1292b6ebb8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_019ebe77-3cfe-7ad0-8f28-dc406579f54d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-7ce3-b6fb-3962a7325382" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_019ebe77-3cfe-7ad0-8f28-dc406579f54d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_019ebe77-3cfe-7ea3-bb21-1905bd67f574" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_019ebe77-3cfe-7ad0-8f28-dc406579f54d" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_019ebe77-3cfe-7ea3-bb21-1905bd67f574" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_019ebe77-3cfe-7623-979b-79ce6b12049f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_019ebe77-3cfe-7ad0-8f28-dc406579f54d" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_019ebe77-3cfe-7623-979b-79ce6b12049f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_019ebe77-3cfe-7320-a4c5-fcdda13bb81c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_019ebe77-3cfe-7ad0-8f28-dc406579f54d" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_019ebe77-3cfe-7320-a4c5-fcdda13bb81c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_019f663f-ad2a-7757-a53e-768e2e33ab90" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_019ebe77-3cfe-7ad0-8f28-dc406579f54d" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_019f663f-ad2a-7757-a53e-768e2e33ab90" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_019ebe77-3cfe-7f51-a476-c02f95ff588b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpectedToVestWeightedAverageGrantDateFairValue_019ebe77-3cfe-7944-85e8-216c119ce850" xlink:href="fn-20260626.xsd#fn_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpectedToVestWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-7ce3-b6fb-3962a7325382" xlink:to="loc_fn_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpectedToVestWeightedAverageGrantDateFairValue_019ebe77-3cfe-7944-85e8-216c119ce850" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/SharebasedcompensationScheduleofEstimatedAssumptionsinPerShareFairValueCalculationDetails" xlink:type="simple" xlink:href="fn-20260626.xsd#SharebasedcompensationScheduleofEstimatedAssumptionsinPerShareFairValueCalculationDetails"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/SharebasedcompensationScheduleofEstimatedAssumptionsinPerShareFairValueCalculationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-7d96-b448-26edd9906013" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019ebe77-3cfe-7752-9398-df06598f5a83" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-7d96-b448-26edd9906013" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019ebe77-3cfe-7752-9398-df06598f5a83" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_019ebe77-3cfe-7830-91a5-95758e4401b2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019ebe77-3cfe-7752-9398-df06598f5a83" xlink:to="loc_us-gaap_AwardTypeAxis_019ebe77-3cfe-7830-91a5-95758e4401b2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019ebe77-3cfe-7830-91a5-95758e4401b2_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_019ebe77-3cfe-7830-91a5-95758e4401b2" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019ebe77-3cfe-7830-91a5-95758e4401b2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019ebe77-3cfe-719a-86f2-f5c983737d02" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_019ebe77-3cfe-7830-91a5-95758e4401b2" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019ebe77-3cfe-719a-86f2-f5c983737d02" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WarrantMember_019ebe77-3cfe-7e37-9585-1801443eb041" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_WarrantMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019ebe77-3cfe-719a-86f2-f5c983737d02" xlink:to="loc_us-gaap_WarrantMember_019ebe77-3cfe-7e37-9585-1801443eb041" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_019ebe77-3cfe-7069-93bc-af46dea7717a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-7d96-b448-26edd9906013" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_019ebe77-3cfe-7069-93bc-af46dea7717a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate_019ebe77-3cfe-7a8e-b195-10dd102b9c5a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-7d96-b448-26edd9906013" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate_019ebe77-3cfe-7a8e-b195-10dd102b9c5a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate_019ebe77-3cfe-7a6c-9ccd-52796354feba" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-7d96-b448-26edd9906013" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate_019ebe77-3cfe-7a6c-9ccd-52796354feba" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_019ebe77-3cfe-7ae2-ab06-107ab3746313" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019ebe77-3cfe-7d96-b448-26edd9906013" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_019ebe77-3cfe-7ae2-ab06-107ab3746313" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/EmployeebenefitplansDetails" xlink:type="simple" xlink:href="fn-20260626.xsd#EmployeebenefitplansDetails"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/EmployeebenefitplansDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_fn_DefinedContributionAndDefinedBenefitPlansLineItems_019ebe77-3cfe-7d30-824e-8399d0cb707f" xlink:href="fn-20260626.xsd#fn_DefinedContributionAndDefinedBenefitPlansLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable_019ebe77-3cfe-775d-b3a2-5cef2f40491c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_fn_DefinedContributionAndDefinedBenefitPlansLineItems_019ebe77-3cfe-7d30-824e-8399d0cb707f" xlink:to="loc_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable_019ebe77-3cfe-775d-b3a2-5cef2f40491c" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetirementPlanTypeAxis_019ebe77-3cfe-7bdb-a238-6e895c75c6e9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RetirementPlanTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable_019ebe77-3cfe-775d-b3a2-5cef2f40491c" xlink:to="loc_us-gaap_RetirementPlanTypeAxis_019ebe77-3cfe-7bdb-a238-6e895c75c6e9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetirementPlanTypeDomain_019ebe77-3cfe-7bdb-a238-6e895c75c6e9_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RetirementPlanTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RetirementPlanTypeAxis_019ebe77-3cfe-7bdb-a238-6e895c75c6e9" xlink:to="loc_us-gaap_RetirementPlanTypeDomain_019ebe77-3cfe-7bdb-a238-6e895c75c6e9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetirementPlanTypeDomain_019ebe77-3cfe-7837-93b5-5de92389a4f3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RetirementPlanTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RetirementPlanTypeAxis_019ebe77-3cfe-7bdb-a238-6e895c75c6e9" xlink:to="loc_us-gaap_RetirementPlanTypeDomain_019ebe77-3cfe-7837-93b5-5de92389a4f3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_ProvidentFundMember_019ebe77-3cfe-79a4-b756-abd5e2aada13" xlink:href="fn-20260626.xsd#fn_ProvidentFundMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RetirementPlanTypeDomain_019ebe77-3cfe-7837-93b5-5de92389a4f3" xlink:to="loc_fn_ProvidentFundMember_019ebe77-3cfe-79a4-b756-abd5e2aada13" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_DefinedContributionPlan401KMember_019ebe77-3cfe-7b6e-96e1-32126dac7bd2" xlink:href="fn-20260626.xsd#fn_DefinedContributionPlan401KMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RetirementPlanTypeDomain_019ebe77-3cfe-7837-93b5-5de92389a4f3" xlink:to="loc_fn_DefinedContributionPlan401KMember_019ebe77-3cfe-7b6e-96e1-32126dac7bd2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedContributionPlanEmployerDiscretionaryContributionAmount_019ebe77-3cfe-7327-84e7-2e5c85977f08" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedContributionPlanEmployerDiscretionaryContributionAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_DefinedContributionAndDefinedBenefitPlansLineItems_019ebe77-3cfe-7d30-824e-8399d0cb707f" xlink:to="loc_us-gaap_DefinedContributionPlanEmployerDiscretionaryContributionAmount_019ebe77-3cfe-7327-84e7-2e5c85977f08" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedContributionPlanMaximumAnnualContributionsPerEmployeePercent_019ebe77-3cfe-7034-b80b-17c6e9571073" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedContributionPlanMaximumAnnualContributionsPerEmployeePercent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_DefinedContributionAndDefinedBenefitPlansLineItems_019ebe77-3cfe-7d30-824e-8399d0cb707f" xlink:to="loc_us-gaap_DefinedContributionPlanMaximumAnnualContributionsPerEmployeePercent_019ebe77-3cfe-7034-b80b-17c6e9571073" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedContributionPlanEmployerMatchingContributionPercentOfMatch_019ebe77-3cfe-7caf-bffe-9a6094a58e0e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedContributionPlanEmployerMatchingContributionPercentOfMatch"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_DefinedContributionAndDefinedBenefitPlansLineItems_019ebe77-3cfe-7d30-824e-8399d0cb707f" xlink:to="loc_us-gaap_DefinedContributionPlanEmployerMatchingContributionPercentOfMatch_019ebe77-3cfe-7caf-bffe-9a6094a58e0e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent_019ebe77-3cfe-78ee-92a9-d4aa2ac5899c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_DefinedContributionAndDefinedBenefitPlansLineItems_019ebe77-3cfe-7d30-824e-8399d0cb707f" xlink:to="loc_us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent_019ebe77-3cfe-78ee-92a9-d4aa2ac5899c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LaborAndRelatedExpense_019ebe77-3cfe-736f-bce4-928cdb7b1953" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LaborAndRelatedExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_DefinedContributionAndDefinedBenefitPlansLineItems_019ebe77-3cfe-7d30-824e-8399d0cb707f" xlink:to="loc_us-gaap_LaborAndRelatedExpense_019ebe77-3cfe-736f-bce4-928cdb7b1953" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/ShareholdersequityDetails" xlink:type="simple" xlink:href="fn-20260626.xsd#ShareholdersequityDetails"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/ShareholdersequityDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_fn_ShareholdersEquityLineItems_019ebe77-3cfe-7459-ad22-0c2399196d5b" xlink:href="fn-20260626.xsd#fn_ShareholdersEquityLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_ShareholdersEquityTable_019ebe77-3cfe-7ec3-84c8-d32701fd6255" xlink:href="fn-20260626.xsd#fn_ShareholdersEquityTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_fn_ShareholdersEquityLineItems_019ebe77-3cfe-7459-ad22-0c2399196d5b" xlink:to="loc_fn_ShareholdersEquityTable_019ebe77-3cfe-7ec3-84c8-d32701fd6255" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameAxis_019ebe77-3cfe-7990-b154-93cf850ed67d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PlanNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_fn_ShareholdersEquityTable_019ebe77-3cfe-7ec3-84c8-d32701fd6255" xlink:to="loc_us-gaap_PlanNameAxis_019ebe77-3cfe-7990-b154-93cf850ed67d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameDomain_019ebe77-3cfe-7990-b154-93cf850ed67d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PlanNameAxis_019ebe77-3cfe-7990-b154-93cf850ed67d" xlink:to="loc_us-gaap_PlanNameDomain_019ebe77-3cfe-7990-b154-93cf850ed67d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameDomain_019ebe77-3cfe-7072-aa6a-6f14c4f26396" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PlanNameAxis_019ebe77-3cfe-7990-b154-93cf850ed67d" xlink:to="loc_us-gaap_PlanNameDomain_019ebe77-3cfe-7072-aa6a-6f14c4f26396" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_EquityIncentivePlansMember_019ebe77-3cfe-7598-a6c5-b30ac7349abd" xlink:href="fn-20260626.xsd#fn_EquityIncentivePlansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PlanNameDomain_019ebe77-3cfe-7072-aa6a-6f14c4f26396" xlink:to="loc_fn_EquityIncentivePlansMember_019ebe77-3cfe-7598-a6c5-b30ac7349abd" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesAuthorized_019ebe77-3cfe-7878-9832-7774aa2d6f89" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockSharesAuthorized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_ShareholdersEquityLineItems_019ebe77-3cfe-7459-ad22-0c2399196d5b" xlink:to="loc_us-gaap_CommonStockSharesAuthorized_019ebe77-3cfe-7878-9832-7774aa2d6f89" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockParOrStatedValuePerShare_019ebe77-3cfe-71c1-832b-8f5a0ebd0100" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockParOrStatedValuePerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_ShareholdersEquityLineItems_019ebe77-3cfe-7459-ad22-0c2399196d5b" xlink:to="loc_us-gaap_CommonStockParOrStatedValuePerShare_019ebe77-3cfe-71c1-832b-8f5a0ebd0100" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PreferredStockSharesAuthorized_019ebe77-3cfe-7c07-9481-92074d6c9513" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PreferredStockSharesAuthorized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_ShareholdersEquityLineItems_019ebe77-3cfe-7459-ad22-0c2399196d5b" xlink:to="loc_us-gaap_PreferredStockSharesAuthorized_019ebe77-3cfe-7c07-9481-92074d6c9513" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PreferredStockParOrStatedValuePerShare_019ebe77-3cfe-7a50-ad05-5f93dc8b6bf4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PreferredStockParOrStatedValuePerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_ShareholdersEquityLineItems_019ebe77-3cfe-7459-ad22-0c2399196d5b" xlink:to="loc_us-gaap_PreferredStockParOrStatedValuePerShare_019ebe77-3cfe-7a50-ad05-5f93dc8b6bf4" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures_019ebe77-3cfe-7819-a0b5-e485eb3115a7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_ShareholdersEquityLineItems_019ebe77-3cfe-7459-ad22-0c2399196d5b" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures_019ebe77-3cfe-7819-a0b5-e485eb3115a7" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StockRepurchaseProgramAuthorizedAmount1_019ebe77-3cfe-7a3f-bea1-d40ee0eaad79" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_StockRepurchaseProgramAuthorizedAmount1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_ShareholdersEquityLineItems_019ebe77-3cfe-7459-ad22-0c2399196d5b" xlink:to="loc_srt_StockRepurchaseProgramAuthorizedAmount1_019ebe77-3cfe-7a3f-bea1-d40ee0eaad79" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_StockRepurchaseProgramAdditionalAuthorizedRepurchaseAmount_019ebe77-3cfe-78d0-9c04-cb97f4468d81" xlink:href="fn-20260626.xsd#fn_StockRepurchaseProgramAdditionalAuthorizedRepurchaseAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_ShareholdersEquityLineItems_019ebe77-3cfe-7459-ad22-0c2399196d5b" xlink:to="loc_fn_StockRepurchaseProgramAdditionalAuthorizedRepurchaseAmount_019ebe77-3cfe-78d0-9c04-cb97f4468d81" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockSharesAcquired_019ebe77-3cfe-71b8-8d43-ce5670e7aa7d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TreasuryStockSharesAcquired"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_ShareholdersEquityLineItems_019ebe77-3cfe-7459-ad22-0c2399196d5b" xlink:to="loc_us-gaap_TreasuryStockSharesAcquired_019ebe77-3cfe-71b8-8d43-ce5670e7aa7d" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockAcquiredAverageCostPerShare_019ebe77-3cfe-73b1-a062-67e8704fe518" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TreasuryStockAcquiredAverageCostPerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_ShareholdersEquityLineItems_019ebe77-3cfe-7459-ad22-0c2399196d5b" xlink:to="loc_us-gaap_TreasuryStockAcquiredAverageCostPerShare_019ebe77-3cfe-73b1-a062-67e8704fe518" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockValueAcquiredCostMethod_019ebe77-3cfe-7742-bf46-001624b2f21d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TreasuryStockValueAcquiredCostMethod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_ShareholdersEquityLineItems_019ebe77-3cfe-7459-ad22-0c2399196d5b" xlink:to="loc_us-gaap_TreasuryStockValueAcquiredCostMethod_019ebe77-3cfe-7742-bf46-001624b2f21d" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1_019ebe77-3cfe-7ae9-9189-70a32ec2ef52" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_ShareholdersEquityLineItems_019ebe77-3cfe-7459-ad22-0c2399196d5b" xlink:to="loc_us-gaap_StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1_019ebe77-3cfe-7ae9-9189-70a32ec2ef52" xlink:type="arc" order="10"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/AccumulatedothercomprehensiveincomelossAOCIScheduleofChangesinAOCINetofTaxDetails" xlink:type="simple" xlink:href="fn-20260626.xsd#AccumulatedothercomprehensiveincomelossAOCIScheduleofChangesinAOCINetofTaxDetails"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/AccumulatedothercomprehensiveincomelossAOCIScheduleofChangesinAOCINetofTaxDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_019ebe77-3cfe-7ac0-8e6e-9cc01f3924a4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_019ebe77-3cfe-739f-9517-18a70fad452e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_019ebe77-3cfe-7ac0-8e6e-9cc01f3924a4" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_019ebe77-3cfe-739f-9517-18a70fad452e" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PartnerCapitalComponentsAxis_019ebe77-3cfe-7dc4-8d88-a5c953d5204c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PartnerCapitalComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_019ebe77-3cfe-739f-9517-18a70fad452e" xlink:to="loc_us-gaap_PartnerCapitalComponentsAxis_019ebe77-3cfe-7dc4-8d88-a5c953d5204c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PartnerCapitalComponentsDomain_019ebe77-3cfe-7dc4-8d88-a5c953d5204c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PartnerCapitalComponentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PartnerCapitalComponentsAxis_019ebe77-3cfe-7dc4-8d88-a5c953d5204c" xlink:to="loc_us-gaap_PartnerCapitalComponentsDomain_019ebe77-3cfe-7dc4-8d88-a5c953d5204c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PartnerCapitalComponentsDomain_019ebe77-3cfe-7e10-a430-4259c14a5422" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PartnerCapitalComponentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PartnerCapitalComponentsAxis_019ebe77-3cfe-7dc4-8d88-a5c953d5204c" xlink:to="loc_us-gaap_PartnerCapitalComponentsDomain_019ebe77-3cfe-7e10-a430-4259c14a5422" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_019ebe77-3cfe-7e00-af4b-a6f07c4b878d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PartnerCapitalComponentsDomain_019ebe77-3cfe-7e10-a430-4259c14a5422" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_019ebe77-3cfe-7e00-af4b-a6f07c4b878d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember_019ebe77-3cfe-7463-9f46-8ed63e7202d7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_019ebe77-3cfe-7e00-af4b-a6f07c4b878d" xlink:to="loc_us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember_019ebe77-3cfe-7463-9f46-8ed63e7202d7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedGainLossNetCashFlowHedgeParentMember_019ebe77-3cfe-7d3c-8453-61bb1a2c524f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedGainLossNetCashFlowHedgeParentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_019ebe77-3cfe-7e00-af4b-a6f07c4b878d" xlink:to="loc_us-gaap_AccumulatedGainLossNetCashFlowHedgeParentMember_019ebe77-3cfe-7d3c-8453-61bb1a2c524f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedTranslationAdjustmentMember_019ebe77-3cfe-77d8-b7e5-db709fd3cf82" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedTranslationAdjustmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_019ebe77-3cfe-7e00-af4b-a6f07c4b878d" xlink:to="loc_us-gaap_AccumulatedTranslationAdjustmentMember_019ebe77-3cfe-77d8-b7e5-db709fd3cf82" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_019ebe77-3cfe-7499-a7f8-36d83b5511be" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AOCIAttributableToParentNetOfTaxRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_019ebe77-3cfe-7ac0-8e6e-9cc01f3924a4" xlink:to="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_019ebe77-3cfe-7499-a7f8-36d83b5511be" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_019ebe77-3cfe-7cdc-bc38-7157120f2dac" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_019ebe77-3cfe-7499-a7f8-36d83b5511be" xlink:to="loc_us-gaap_StockholdersEquity_019ebe77-3cfe-7cdc-bc38-7157120f2dac" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OciBeforeReclassificationsBeforeTaxAttributableToParent_019ebe77-3cfe-77a3-a9d8-1e981ca61177" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OciBeforeReclassificationsBeforeTaxAttributableToParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_019ebe77-3cfe-7499-a7f8-36d83b5511be" xlink:to="loc_us-gaap_OciBeforeReclassificationsBeforeTaxAttributableToParent_019ebe77-3cfe-77a3-a9d8-1e981ca61177" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationFromAociCurrentPeriodBeforeTaxAttributableToParent_019ebe77-3cfe-7904-8712-bf8c72de0a3a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ReclassificationFromAociCurrentPeriodBeforeTaxAttributableToParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_019ebe77-3cfe-7499-a7f8-36d83b5511be" xlink:to="loc_us-gaap_ReclassificationFromAociCurrentPeriodBeforeTaxAttributableToParent_019ebe77-3cfe-7904-8712-bf8c72de0a3a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossTaxPortionAttributableToParent1_019ebe77-3cfe-702f-a0c0-0f09ce110eb4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossTaxPortionAttributableToParent1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_019ebe77-3cfe-7499-a7f8-36d83b5511be" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossTaxPortionAttributableToParent1_019ebe77-3cfe-702f-a0c0-0f09ce110eb4" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_019ebe77-3cfe-7fcf-b19d-1b068be9e6bd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_019ebe77-3cfe-7499-a7f8-36d83b5511be" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_019ebe77-3cfe-7fcf-b19d-1b068be9e6bd" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_019ebe77-3cfe-71ec-a7a6-a0d3eea2bbad" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquity"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/AccumulatedothercomprehensiveincomelossAOCIScheduleofPreTaxAmountsReclassifiedfromAOCIintoCondensedConsolidatedStatementsofOperationsandComprehensiveIncomeDetails" xlink:type="simple" xlink:href="fn-20260626.xsd#AccumulatedothercomprehensiveincomelossAOCIScheduleofPreTaxAmountsReclassifiedfromAOCIintoCondensedConsolidatedStatementsofOperationsandComprehensiveIncomeDetails"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/AccumulatedothercomprehensiveincomelossAOCIScheduleofPreTaxAmountsReclassifiedfromAOCIintoCondensedConsolidatedStatementsofOperationsandComprehensiveIncomeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems_019ebe77-3cfe-7aec-a950-012d8f772fcd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTable_019ebe77-3cfe-7ff0-b83f-1a68412fe415" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems_019ebe77-3cfe-7aec-a950-012d8f772fcd" xlink:to="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTable_019ebe77-3cfe-7ff0-b83f-1a68412fe415" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis_019ebe77-3cfe-7611-99ba-6dee5aa906a7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTable_019ebe77-3cfe-7ff0-b83f-1a68412fe415" xlink:to="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis_019ebe77-3cfe-7611-99ba-6dee5aa906a7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain_019ebe77-3cfe-7611-99ba-6dee5aa906a7_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis_019ebe77-3cfe-7611-99ba-6dee5aa906a7" xlink:to="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain_019ebe77-3cfe-7611-99ba-6dee5aa906a7_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain_019ebe77-3cfe-7c4b-bc0c-225acb75a63d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis_019ebe77-3cfe-7611-99ba-6dee5aa906a7" xlink:to="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain_019ebe77-3cfe-7c4b-bc0c-225acb75a63d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember_019ebe77-3cfe-727d-b173-e9487154f70b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain_019ebe77-3cfe-7c4b-bc0c-225acb75a63d" xlink:to="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember_019ebe77-3cfe-727d-b173-e9487154f70b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementOfIncomeLocationBalanceAxis_019ebe77-3cfe-7c76-aab2-d8af8337de7b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementOfIncomeLocationBalanceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTable_019ebe77-3cfe-7ff0-b83f-1a68412fe415" xlink:to="loc_us-gaap_StatementOfIncomeLocationBalanceAxis_019ebe77-3cfe-7c76-aab2-d8af8337de7b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax_019ebe77-3cfe-72e1-924e-bccb935ab86e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems_019ebe77-3cfe-7aec-a950-012d8f772fcd" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax_019ebe77-3cfe-72e1-924e-bccb935ab86e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationFromAociCurrentPeriodBeforeTaxAttributableToParent_019ebe77-3cfe-752f-ab27-e11a73b5804c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ReclassificationFromAociCurrentPeriodBeforeTaxAttributableToParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems_019ebe77-3cfe-7aec-a950-012d8f772fcd" xlink:to="loc_us-gaap_ReclassificationFromAociCurrentPeriodBeforeTaxAttributableToParent_019ebe77-3cfe-752f-ab27-e11a73b5804c" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/AccumulatedothercomprehensiveincomelossAOCIScheduleofPreTaxAmountsReclassifiedfromAOCIintoCondensedConsolidatedStatementsofOperationsandComprehensiveIncomeDetails_1" xlink:type="simple" xlink:href="fn-20260626.xsd#AccumulatedothercomprehensiveincomelossAOCIScheduleofPreTaxAmountsReclassifiedfromAOCIintoCondensedConsolidatedStatementsofOperationsandComprehensiveIncomeDetails_1"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/AccumulatedothercomprehensiveincomelossAOCIScheduleofPreTaxAmountsReclassifiedfromAOCIintoCondensedConsolidatedStatementsofOperationsandComprehensiveIncomeDetails_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems_019ebe77-3cfe-7aec-a950-012d8f772fcd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTable_019ebe77-3cfe-7ff0-b83f-1a68412fe415" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems_019ebe77-3cfe-7aec-a950-012d8f772fcd" xlink:to="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTable_019ebe77-3cfe-7ff0-b83f-1a68412fe415" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis_019ebe77-3cfe-7611-99ba-6dee5aa906a7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTable_019ebe77-3cfe-7ff0-b83f-1a68412fe415" xlink:to="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis_019ebe77-3cfe-7611-99ba-6dee5aa906a7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain_019ebe77-3cfe-7611-99ba-6dee5aa906a7_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis_019ebe77-3cfe-7611-99ba-6dee5aa906a7" xlink:to="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain_019ebe77-3cfe-7611-99ba-6dee5aa906a7_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain_019ebe77-3cfe-7c4b-bc0c-225acb75a63d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis_019ebe77-3cfe-7611-99ba-6dee5aa906a7" xlink:to="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain_019ebe77-3cfe-7c4b-bc0c-225acb75a63d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember_019ebe77-3cfe-727d-b173-e9487154f70b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain_019ebe77-3cfe-7c4b-bc0c-225acb75a63d" xlink:to="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember_019ebe77-3cfe-727d-b173-e9487154f70b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax_019ebe77-3cfe-72e1-924e-bccb935ab86e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems_019ebe77-3cfe-7aec-a950-012d8f772fcd" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax_019ebe77-3cfe-72e1-924e-bccb935ab86e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationFromAociCurrentPeriodBeforeTaxAttributableToParent_019ebe77-3cfe-752f-ab27-e11a73b5804c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ReclassificationFromAociCurrentPeriodBeforeTaxAttributableToParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems_019ebe77-3cfe-7aec-a950-012d8f772fcd" xlink:to="loc_us-gaap_ReclassificationFromAociCurrentPeriodBeforeTaxAttributableToParent_019ebe77-3cfe-752f-ab27-e11a73b5804c" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/CommitmentsandcontingenciesDetails" xlink:type="simple" xlink:href="fn-20260626.xsd#CommitmentsandcontingenciesDetails"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/CommitmentsandcontingenciesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingenciesLineItems_019f6644-e910-77b1-bf70-3e2480c95b57" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LossContingenciesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingenciesTable_019ebe77-3cfe-7271-a442-67d98c1ccd74" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LossContingenciesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LossContingenciesLineItems_019f6644-e910-77b1-bf70-3e2480c95b57" xlink:to="loc_us-gaap_LossContingenciesTable_019ebe77-3cfe-7271-a442-67d98c1ccd74" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchasedAxis_019f6644-e910-7f59-b9c9-6864960b113a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchasedAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_019ebe77-3cfe-7271-a442-67d98c1ccd74" xlink:to="loc_us-gaap_UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchasedAxis_019f6644-e910-7f59-b9c9-6864960b113a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnconditionalPurchaseObligationCategoryOfGoodsOrServicesAcquiredDomain_019f6644-e910-7f59-b9c9-6864960b113a_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_UnconditionalPurchaseObligationCategoryOfGoodsOrServicesAcquiredDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchasedAxis_019f6644-e910-7f59-b9c9-6864960b113a" xlink:to="loc_us-gaap_UnconditionalPurchaseObligationCategoryOfGoodsOrServicesAcquiredDomain_019f6644-e910-7f59-b9c9-6864960b113a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnconditionalPurchaseObligationCategoryOfGoodsOrServicesAcquiredDomain_019f6644-e910-70e9-9e99-cd99e0b6402c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_UnconditionalPurchaseObligationCategoryOfGoodsOrServicesAcquiredDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchasedAxis_019f6644-e910-7f59-b9c9-6864960b113a" xlink:to="loc_us-gaap_UnconditionalPurchaseObligationCategoryOfGoodsOrServicesAcquiredDomain_019f6644-e910-70e9-9e99-cd99e0b6402c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoriesMember_019f6644-e910-7662-b9f6-821c249fcb89" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InventoriesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_UnconditionalPurchaseObligationCategoryOfGoodsOrServicesAcquiredDomain_019f6644-e910-70e9-9e99-cd99e0b6402c" xlink:to="loc_us-gaap_InventoriesMember_019f6644-e910-7662-b9f6-821c249fcb89" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_019f6644-e910-7456-9fe6-7a2a289dcd8b" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_019ebe77-3cfe-7271-a442-67d98c1ccd74" xlink:to="loc_srt_StatementGeographicalAxis_019f6644-e910-7456-9fe6-7a2a289dcd8b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_019f6644-e910-7456-9fe6-7a2a289dcd8b_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_019f6644-e910-7456-9fe6-7a2a289dcd8b" xlink:to="loc_srt_SegmentGeographicalDomain_019f6644-e910-7456-9fe6-7a2a289dcd8b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_019f6644-e910-7478-8300-bbcfd35d26ca" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_019f6644-e910-7456-9fe6-7a2a289dcd8b" xlink:to="loc_srt_SegmentGeographicalDomain_019f6644-e910-7478-8300-bbcfd35d26ca" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_TH_019f6644-e910-7a7f-83d9-278e574c6a43" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_TH"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_019f6644-e910-7478-8300-bbcfd35d26ca" xlink:to="loc_country_TH_019f6644-e910-7a7f-83d9-278e574c6a43" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_CN_019fc729-761e-706f-9bbf-3ef8288497a2" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_CN"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_019f6644-e910-7478-8300-bbcfd35d26ca" xlink:to="loc_country_CN_019fc729-761e-706f-9bbf-3ef8288497a2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_019f6644-e910-7c76-a4f1-6e1b5db41e04" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_019ebe77-3cfe-7271-a442-67d98c1ccd74" xlink:to="loc_us-gaap_DebtInstrumentAxis_019f6644-e910-7c76-a4f1-6e1b5db41e04" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019f6644-e910-7c76-a4f1-6e1b5db41e04_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_019f6644-e910-7c76-a4f1-6e1b5db41e04" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019f6644-e910-7c76-a4f1-6e1b5db41e04_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019f6644-e910-7477-8e47-c1b6dda9801d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_019f6644-e910-7c76-a4f1-6e1b5db41e04" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019f6644-e910-7477-8e47-c1b6dda9801d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_A2023CreditFacilityAgreementMember_019f6644-e910-7b37-9704-d44359ffd4e1" xlink:href="fn-20260626.xsd#fn_A2023CreditFacilityAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019f6644-e910-7477-8e47-c1b6dda9801d" xlink:to="loc_fn_A2023CreditFacilityAgreementMember_019f6644-e910-7b37-9704-d44359ffd4e1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_BankGuaranteesMember_019fd001-c983-7810-8cf9-45764f1262e3" xlink:href="fn-20260626.xsd#fn_BankGuaranteesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019f6644-e910-7477-8e47-c1b6dda9801d" xlink:to="loc_fn_BankGuaranteesMember_019fd001-c983-7810-8cf9-45764f1262e3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_019f6644-e910-72b8-a9dd-fabe9ec9345e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_019ebe77-3cfe-7271-a442-67d98c1ccd74" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_019f6644-e910-72b8-a9dd-fabe9ec9345e" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019f6644-e910-72b8-a9dd-fabe9ec9345e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_019f6644-e910-72b8-a9dd-fabe9ec9345e" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019f6644-e910-72b8-a9dd-fabe9ec9345e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019f6644-e910-7ad7-9527-e2154d70a49a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_019f6644-e910-72b8-a9dd-fabe9ec9345e" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019f6644-e910-7ad7-9527-e2154d70a49a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditMember_019f6644-e910-7611-94a0-c185e733ba46" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_019f6644-e910-7ad7-9527-e2154d70a49a" xlink:to="loc_us-gaap_LineOfCreditMember_019f6644-e910-7611-94a0-c185e733ba46" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_LitigationCaseAxis_019fcffe-ecdd-7052-a9ca-6be49405b246" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_LitigationCaseAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_019ebe77-3cfe-7271-a442-67d98c1ccd74" xlink:to="loc_srt_LitigationCaseAxis_019fcffe-ecdd-7052-a9ca-6be49405b246" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_LitigationCaseTypeDomain_019fcffe-ecdd-7052-a9ca-6be49405b246_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_LitigationCaseTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_LitigationCaseAxis_019fcffe-ecdd-7052-a9ca-6be49405b246" xlink:to="loc_srt_LitigationCaseTypeDomain_019fcffe-ecdd-7052-a9ca-6be49405b246_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_LitigationCaseTypeDomain_019fcffe-ecdd-7f40-ac02-bda6ce3ad85b" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_LitigationCaseTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_LitigationCaseAxis_019fcffe-ecdd-7052-a9ca-6be49405b246" xlink:to="loc_srt_LitigationCaseTypeDomain_019fcffe-ecdd-7f40-ac02-bda6ce3ad85b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_NganInLengAndFirstLaserLimitedMember_019fcfff-25d2-74ad-b46f-a87f56b2fe99" xlink:href="fn-20260626.xsd#fn_NganInLengAndFirstLaserLimitedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_LitigationCaseTypeDomain_019fcffe-ecdd-7f40-ac02-bda6ce3ad85b" xlink:to="loc_fn_NganInLengAndFirstLaserLimitedMember_019fcfff-25d2-74ad-b46f-a87f56b2fe99" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeAxis_019fd9f7-d74d-7fc4-aeb5-540913449bc2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_019ebe77-3cfe-7271-a442-67d98c1ccd74" xlink:to="loc_us-gaap_SubsequentEventTypeAxis_019fd9f7-d74d-7fc4-aeb5-540913449bc2" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_019fd9f7-d74d-7fc4-aeb5-540913449bc2_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_019fd9f7-d74d-7fc4-aeb5-540913449bc2" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_019fd9f7-d74d-7fc4-aeb5-540913449bc2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_019fd9f7-d74d-7ce6-9101-8379597b8fb4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_019fd9f7-d74d-7fc4-aeb5-540913449bc2" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_019fd9f7-d74d-7ce6-9101-8379597b8fb4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventMember_019fd9f7-f7f9-738a-9fec-c0f0975fcb2c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventTypeDomain_019fd9f7-d74d-7ce6-9101-8379597b8fb4" xlink:to="loc_us-gaap_SubsequentEventMember_019fd9f7-f7f9-738a-9fec-c0f0975fcb2c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityAxis_019fda03-0340-73f9-83dd-4c658b3b3121" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_019ebe77-3cfe-7271-a442-67d98c1ccd74" xlink:to="loc_us-gaap_LineOfCreditFacilityAxis_019fda03-0340-73f9-83dd-4c658b3b3121" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityLenderDomain_019fda03-0340-73f9-83dd-4c658b3b3121_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityLenderDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LineOfCreditFacilityAxis_019fda03-0340-73f9-83dd-4c658b3b3121" xlink:to="loc_us-gaap_LineOfCreditFacilityLenderDomain_019fda03-0340-73f9-83dd-4c658b3b3121_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityLenderDomain_019fda03-0340-7c19-a4ea-d8c579ad8a9d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityLenderDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LineOfCreditFacilityAxis_019fda03-0340-73f9-83dd-4c658b3b3121" xlink:to="loc_us-gaap_LineOfCreditFacilityLenderDomain_019fda03-0340-7c19-a4ea-d8c579ad8a9d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_BankOfAyudhyaPublicCompanyLimitedMember_019fda03-0340-7524-ad1a-8a7b279974b7" xlink:href="fn-20260626.xsd#fn_BankOfAyudhyaPublicCompanyLimitedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLenderDomain_019fda03-0340-7c19-a4ea-d8c579ad8a9d" xlink:to="loc_fn_BankOfAyudhyaPublicCompanyLimitedMember_019fda03-0340-7524-ad1a-8a7b279974b7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TypeOfArrangementAxis_019fda03-0340-7e2d-be55-5707efd47ede" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TypeOfArrangementAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_019ebe77-3cfe-7271-a442-67d98c1ccd74" xlink:to="loc_us-gaap_TypeOfArrangementAxis_019fda03-0340-7e2d-be55-5707efd47ede" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ArrangementsAndNonarrangementTransactionsMember_019fda03-0340-7e2d-be55-5707efd47ede_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ArrangementsAndNonarrangementTransactionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_TypeOfArrangementAxis_019fda03-0340-7e2d-be55-5707efd47ede" xlink:to="loc_us-gaap_ArrangementsAndNonarrangementTransactionsMember_019fda03-0340-7e2d-be55-5707efd47ede_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ArrangementsAndNonarrangementTransactionsMember_019fda03-0340-7bb1-a216-b5d9abf5c192" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ArrangementsAndNonarrangementTransactionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_TypeOfArrangementAxis_019fda03-0340-7e2d-be55-5707efd47ede" xlink:to="loc_us-gaap_ArrangementsAndNonarrangementTransactionsMember_019fda03-0340-7bb1-a216-b5d9abf5c192" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_CreditFacilityAgreementMember_019fda03-0340-76f5-816d-3b742718c584" xlink:href="fn-20260626.xsd#fn_CreditFacilityAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ArrangementsAndNonarrangementTransactionsMember_019fda03-0340-7bb1-a216-b5d9abf5c192" xlink:to="loc_fn_CreditFacilityAgreementMember_019fda03-0340-76f5-816d-3b742718c584" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GuaranteeObligationsCurrentCarryingValue_019f6644-e910-7401-a694-8fec885c19bb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GuaranteeObligationsCurrentCarryingValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_019f6644-e910-77b1-bf70-3e2480c95b57" xlink:to="loc_us-gaap_GuaranteeObligationsCurrentCarryingValue_019f6644-e910-7401-a694-8fec885c19bb" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentCollateralAmount_019fd001-3fb9-7bc2-8f73-5c56748f73e0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentCollateralAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_019f6644-e910-77b1-bf70-3e2480c95b57" xlink:to="loc_us-gaap_DebtInstrumentCollateralAmount_019fd001-3fb9-7bc2-8f73-5c56748f73e0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PurchaseObligation_019f6644-e910-7bf7-ade3-7a2c1076bf54" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PurchaseObligation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_019f6644-e910-77b1-bf70-3e2480c95b57" xlink:to="loc_us-gaap_PurchaseObligation_019f6644-e910-7bf7-ade3-7a2c1076bf54" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_019f6644-e910-723e-8552-b223acc1c5c9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_019f6644-e910-77b1-bf70-3e2480c95b57" xlink:to="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_019f6644-e910-723e-8552-b223acc1c5c9" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromLongTermLinesOfCredit_019fea82-ef98-7ae6-98f2-0bc4888edc7c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromLongTermLinesOfCredit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_019f6644-e910-77b1-bf70-3e2480c95b57" xlink:to="loc_us-gaap_ProceedsFromLongTermLinesOfCredit_019fea82-ef98-7ae6-98f2-0bc4888edc7c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebt_019f6644-e910-7e13-9c49-e216ad23a00e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_019f6644-e910-77b1-bf70-3e2480c95b57" xlink:to="loc_us-gaap_LongTermDebt_019f6644-e910-7e13-9c49-e216ad23a00e" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_DebtInstrumentCovenantServiceCoverageRatioMinimumAtPaymentOfADividend_019f6644-e910-7eb7-add6-1ff1839b12f6" xlink:href="fn-20260626.xsd#fn_DebtInstrumentCovenantServiceCoverageRatioMinimumAtPaymentOfADividend"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_019f6644-e910-77b1-bf70-3e2480c95b57" xlink:to="loc_fn_DebtInstrumentCovenantServiceCoverageRatioMinimumAtPaymentOfADividend_019f6644-e910-7eb7-add6-1ff1839b12f6" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_DebtInstrumentCovenantDebtToEquityRatioMaximum_019f6644-e910-7f88-8061-ac4d7a4e42c7" xlink:href="fn-20260626.xsd#fn_DebtInstrumentCovenantDebtToEquityRatioMaximum"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_019f6644-e910-77b1-bf70-3e2480c95b57" xlink:to="loc_fn_DebtInstrumentCovenantDebtToEquityRatioMaximum_019f6644-e910-7f88-8061-ac4d7a4e42c7" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossContingencyDamagesSoughtValue_019fcffd-6ca9-781c-8506-094fc976a35b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LossContingencyDamagesSoughtValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_019f6644-e910-77b1-bf70-3e2480c95b57" xlink:to="loc_us-gaap_LossContingencyDamagesSoughtValue_019fcffd-6ca9-781c-8506-094fc976a35b" xlink:type="arc" order="8"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/BusinesssegmentsandgeographicinformationSegmentreportingofRevenueandSignificantExpensesDetails" xlink:type="simple" xlink:href="fn-20260626.xsd#BusinesssegmentsandgeographicinformationSegmentreportingofRevenueandSignificantExpensesDetails"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/BusinesssegmentsandgeographicinformationSegmentreportingofRevenueandSignificantExpensesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_019ff8a7-4b7e-76b4-95a8-e3478f88399a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentReportingInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_019ff8a7-4b7e-7e13-89b3-2eb9e256e3e0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019ff8a7-4b7e-76b4-95a8-e3478f88399a" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_019ff8a7-4b7e-7e13-89b3-2eb9e256e3e0" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_019ff8a7-4b7e-7389-90a4-7b12c37cc6dc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_019ff8a7-4b7e-7e13-89b3-2eb9e256e3e0" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_019ff8a7-4b7e-7389-90a4-7b12c37cc6dc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_019ff8a7-4b7e-7389-90a4-7b12c37cc6dc_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_019ff8a7-4b7e-7389-90a4-7b12c37cc6dc" xlink:to="loc_us-gaap_SegmentDomain_019ff8a7-4b7e-7389-90a4-7b12c37cc6dc_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_019ff8a7-4b7e-72fa-b315-c0df5b105d1e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_019ff8a7-4b7e-7389-90a4-7b12c37cc6dc" xlink:to="loc_us-gaap_SegmentDomain_019ff8a7-4b7e-72fa-b315-c0df5b105d1e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_ReportableSegmentMember_019ff8a7-8ece-73fd-bfb7-870bbe405f7c" xlink:href="fn-20260626.xsd#fn_ReportableSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019ff8a7-4b7e-72fa-b315-c0df5b105d1e" xlink:to="loc_fn_ReportableSegmentMember_019ff8a7-8ece-73fd-bfb7-870bbe405f7c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Revenues_019ebe77-3cfe-7e92-b42b-f7a1df47ef6f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Revenues"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019ff8a7-4b7e-76b4-95a8-e3478f88399a" xlink:to="loc_us-gaap_Revenues_019ebe77-3cfe-7e92-b42b-f7a1df47ef6f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostOfRevenue_019ebe77-3cfe-70a5-a5b1-6c6cb74e0ca5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CostOfRevenue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019ff8a7-4b7e-76b4-95a8-e3478f88399a" xlink:to="loc_us-gaap_CostOfRevenue_019ebe77-3cfe-70a5-a5b1-6c6cb74e0ca5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GrossProfit_019ebe77-3cfe-7abe-be38-225050a35080" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GrossProfit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019ff8a7-4b7e-76b4-95a8-e3478f88399a" xlink:to="loc_us-gaap_GrossProfit_019ebe77-3cfe-7abe-be38-225050a35080" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SellingGeneralAndAdministrativeExpense_019ebe77-3cfe-7ca3-9299-956f18423a00" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SellingGeneralAndAdministrativeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019ff8a7-4b7e-76b4-95a8-e3478f88399a" xlink:to="loc_us-gaap_SellingGeneralAndAdministrativeExpense_019ebe77-3cfe-7ca3-9299-956f18423a00" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringCharges_019ebe77-3cfe-7461-88bf-5d38837c5f33" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestructuringCharges"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019ff8a7-4b7e-76b4-95a8-e3478f88399a" xlink:to="loc_us-gaap_RestructuringCharges_019ebe77-3cfe-7461-88bf-5d38837c5f33" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingIncomeLoss_019ebe77-3cfe-7a7c-9d4c-268d315c7d2a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019ff8a7-4b7e-76b4-95a8-e3478f88399a" xlink:to="loc_us-gaap_OperatingIncomeLoss_019ebe77-3cfe-7a7c-9d4c-268d315c7d2a" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestAndOtherIncome_019ebe77-3cfe-780d-b4ec-0bd4a1182dfe" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestAndOtherIncome"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019ff8a7-4b7e-76b4-95a8-e3478f88399a" xlink:to="loc_us-gaap_InterestAndOtherIncome_019ebe77-3cfe-780d-b4ec-0bd4a1182dfe" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseNonoperating_019ebe77-3cfe-7ae6-8d56-07fa6c1a4729" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestExpenseNonoperating"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019ff8a7-4b7e-76b4-95a8-e3478f88399a" xlink:to="loc_us-gaap_InterestExpenseNonoperating_019ebe77-3cfe-7ae6-8d56-07fa6c1a4729" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignCurrencyTransactionGainLossBeforeTax_019ebe77-3cfe-7f6b-a3a6-1c939bfa1828" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignCurrencyTransactionGainLossBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019ff8a7-4b7e-76b4-95a8-e3478f88399a" xlink:to="loc_us-gaap_ForeignCurrencyTransactionGainLossBeforeTax_019ebe77-3cfe-7f6b-a3a6-1c939bfa1828" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherNonoperatingIncomeExpense_019ebe77-3cfe-70e6-aa41-a87125365dda" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherNonoperatingIncomeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019ff8a7-4b7e-76b4-95a8-e3478f88399a" xlink:to="loc_us-gaap_OtherNonoperatingIncomeExpense_019ebe77-3cfe-70e6-aa41-a87125365dda" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019ebe77-3cfe-7b20-b6a2-f1497cc5581b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019ff8a7-4b7e-76b4-95a8-e3478f88399a" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019ebe77-3cfe-7b20-b6a2-f1497cc5581b" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_019ebe77-3cfe-7889-abfc-1c48f1b4563c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxExpenseBenefit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019ff8a7-4b7e-76b4-95a8-e3478f88399a" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_019ebe77-3cfe-7889-abfc-1c48f1b4563c" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_019ebe77-3cfe-79d1-9154-8adda4e884a7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019ff8a7-4b7e-76b4-95a8-e3478f88399a" xlink:to="loc_us-gaap_NetIncomeLoss_019ebe77-3cfe-79d1-9154-8adda4e884a7" xlink:type="arc" order="12"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/BusinesssegmentsandgeographicinformationScheduleofLongLivedAssetsbyGeographicAreasDetails" xlink:type="simple" xlink:href="fn-20260626.xsd#BusinesssegmentsandgeographicinformationScheduleofLongLivedAssetsbyGeographicAreasDetails"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/BusinesssegmentsandgeographicinformationScheduleofLongLivedAssetsbyGeographicAreasDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_019ebe77-3cfe-74d8-852e-5ad4dfbad273" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentReportingInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_019ebe77-3cfe-77a9-8bf4-e6a2e039b42a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019ebe77-3cfe-74d8-852e-5ad4dfbad273" xlink:to="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_019ebe77-3cfe-77a9-8bf4-e6a2e039b42a" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_019ebe77-3cfe-7449-8710-3fda82d1a832" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_019ebe77-3cfe-77a9-8bf4-e6a2e039b42a" xlink:to="loc_srt_StatementGeographicalAxis_019ebe77-3cfe-7449-8710-3fda82d1a832" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_019ebe77-3cfe-7449-8710-3fda82d1a832_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_019ebe77-3cfe-7449-8710-3fda82d1a832" xlink:to="loc_srt_SegmentGeographicalDomain_019ebe77-3cfe-7449-8710-3fda82d1a832_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_019ebe77-3cfe-7fa3-b98d-1487efb65656" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_019ebe77-3cfe-7449-8710-3fda82d1a832" xlink:to="loc_srt_SegmentGeographicalDomain_019ebe77-3cfe-7fa3-b98d-1487efb65656" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_TH_019ebe77-3cfe-7c5e-aab2-974cdfa38f8c" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_TH"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_019ebe77-3cfe-7fa3-b98d-1487efb65656" xlink:to="loc_country_TH_019ebe77-3cfe-7c5e-aab2-974cdfa38f8c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_US_019ebe77-3cfe-75f7-8914-a432b4952938" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_US"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_019ebe77-3cfe-7fa3-b98d-1487efb65656" xlink:to="loc_country_US_019ebe77-3cfe-75f7-8914-a432b4952938" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_CN_019ebe77-3cfe-7897-a41b-df91dcf61fef" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_CN"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_019ebe77-3cfe-7fa3-b98d-1487efb65656" xlink:to="loc_country_CN_019ebe77-3cfe-7897-a41b-df91dcf61fef" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_IL_019ebe77-3cfe-7c8f-b9ba-a0fda81e0f27" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_IL"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_019ebe77-3cfe-7fa3-b98d-1487efb65656" xlink:to="loc_country_IL_019ebe77-3cfe-7c8f-b9ba-a0fda81e0f27" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_OthersGeographicAreaMember_019ebe77-3cfe-73b3-af60-846bc9659dac" xlink:href="fn-20260626.xsd#fn_OthersGeographicAreaMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_019ebe77-3cfe-7fa3-b98d-1487efb65656" xlink:to="loc_fn_OthersGeographicAreaMember_019ebe77-3cfe-73b3-af60-846bc9659dac" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoncurrentAssets_019ebe77-3cfe-73ac-9ac8-70a5a1cd6f18" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NoncurrentAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019ebe77-3cfe-74d8-852e-5ad4dfbad273" xlink:to="loc_us-gaap_NoncurrentAssets_019ebe77-3cfe-73ac-9ac8-70a5a1cd6f18" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/BusinesssegmentsandgeographicinformationScheduleofTotalRevenuesbyPercentagefromIndividualCustomersRepresentingTenPercentorMoreofTotalRevenuesDetails" xlink:type="simple" xlink:href="fn-20260626.xsd#BusinesssegmentsandgeographicinformationScheduleofTotalRevenuesbyPercentagefromIndividualCustomersRepresentingTenPercentorMoreofTotalRevenuesDetails"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/BusinesssegmentsandgeographicinformationScheduleofTotalRevenuesbyPercentagefromIndividualCustomersRepresentingTenPercentorMoreofTotalRevenuesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EntityWideRevenueMajorCustomerLineItems_019ebe77-3cfe-7d9a-97c1-1cbbac8947b2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EntityWideRevenueMajorCustomerLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEntityWideRevenueByMajorCustomersByReportingSegmentsTable_019ebe77-3cfe-7375-bced-637183aa9329" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfEntityWideRevenueByMajorCustomersByReportingSegmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_EntityWideRevenueMajorCustomerLineItems_019ebe77-3cfe-7d9a-97c1-1cbbac8947b2" xlink:to="loc_us-gaap_ScheduleOfEntityWideRevenueByMajorCustomersByReportingSegmentsTable_019ebe77-3cfe-7375-bced-637183aa9329" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_019ebe77-3cfe-7d51-8d7b-9830bd8e3ac8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskByBenchmarkAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEntityWideRevenueByMajorCustomersByReportingSegmentsTable_019ebe77-3cfe-7375-bced-637183aa9329" xlink:to="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_019ebe77-3cfe-7d51-8d7b-9830bd8e3ac8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019ebe77-3cfe-7d51-8d7b-9830bd8e3ac8_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_019ebe77-3cfe-7d51-8d7b-9830bd8e3ac8" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019ebe77-3cfe-7d51-8d7b-9830bd8e3ac8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019ebe77-3cfe-74b7-96bc-e63fe55a0037" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_019ebe77-3cfe-7d51-8d7b-9830bd8e3ac8" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019ebe77-3cfe-74b7-96bc-e63fe55a0037" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SalesRevenueNetMember_019ebe77-3cfe-7b31-b6ab-528182518aba" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SalesRevenueNetMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019ebe77-3cfe-74b7-96bc-e63fe55a0037" xlink:to="loc_us-gaap_SalesRevenueNetMember_019ebe77-3cfe-7b31-b6ab-528182518aba" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByTypeAxis_019ebe77-3cfe-7de6-a0bb-f5485e6be6d9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskByTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEntityWideRevenueByMajorCustomersByReportingSegmentsTable_019ebe77-3cfe-7375-bced-637183aa9329" xlink:to="loc_us-gaap_ConcentrationRiskByTypeAxis_019ebe77-3cfe-7de6-a0bb-f5485e6be6d9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_019ebe77-3cfe-7de6-a0bb-f5485e6be6d9_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_019ebe77-3cfe-7de6-a0bb-f5485e6be6d9" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_019ebe77-3cfe-7de6-a0bb-f5485e6be6d9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_019ebe77-3cfe-742a-975c-f4edee2aa586" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_019ebe77-3cfe-7de6-a0bb-f5485e6be6d9" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_019ebe77-3cfe-742a-975c-f4edee2aa586" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CustomerConcentrationRiskMember_019ebe77-3cfe-7062-9e3d-dfdee459c15e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CustomerConcentrationRiskMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskTypeDomain_019ebe77-3cfe-742a-975c-f4edee2aa586" xlink:to="loc_us-gaap_CustomerConcentrationRiskMember_019ebe77-3cfe-7062-9e3d-dfdee459c15e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MajorCustomersAxis_019ebe77-3cfe-7857-8a89-89781f5313ca" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MajorCustomersAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEntityWideRevenueByMajorCustomersByReportingSegmentsTable_019ebe77-3cfe-7375-bced-637183aa9329" xlink:to="loc_srt_MajorCustomersAxis_019ebe77-3cfe-7857-8a89-89781f5313ca" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_NameOfMajorCustomerDomain_019ebe77-3cfe-7857-8a89-89781f5313ca_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_NameOfMajorCustomerDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_MajorCustomersAxis_019ebe77-3cfe-7857-8a89-89781f5313ca" xlink:to="loc_srt_NameOfMajorCustomerDomain_019ebe77-3cfe-7857-8a89-89781f5313ca_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_NameOfMajorCustomerDomain_019ebe77-3cfe-7863-a62c-d1a147fb714d" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_NameOfMajorCustomerDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_MajorCustomersAxis_019ebe77-3cfe-7857-8a89-89781f5313ca" xlink:to="loc_srt_NameOfMajorCustomerDomain_019ebe77-3cfe-7863-a62c-d1a147fb714d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_CiscoSystemsIncMember_019ebe77-3cfe-7656-ba01-0e9689afcde3" xlink:href="fn-20260626.xsd#fn_CiscoSystemsIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NameOfMajorCustomerDomain_019ebe77-3cfe-7863-a62c-d1a147fb714d" xlink:to="loc_fn_CiscoSystemsIncMember_019ebe77-3cfe-7656-ba01-0e9689afcde3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_NvidiaCorporationMember_019ebe77-3cfe-7285-9f93-e21742839223" xlink:href="fn-20260626.xsd#fn_NvidiaCorporationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NameOfMajorCustomerDomain_019ebe77-3cfe-7863-a62c-d1a147fb714d" xlink:to="loc_fn_NvidiaCorporationMember_019ebe77-3cfe-7285-9f93-e21742839223" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_NokiaCorporationMember_019f92f7-3024-744c-9826-6d18a4f4c0a9" xlink:href="fn-20260626.xsd#fn_NokiaCorporationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NameOfMajorCustomerDomain_019ebe77-3cfe-7863-a62c-d1a147fb714d" xlink:to="loc_fn_NokiaCorporationMember_019f92f7-3024-744c-9826-6d18a4f4c0a9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_Amazon.comInc.Member_019f92f7-b4a9-71ef-afdb-1c705ac65f61" xlink:href="fn-20260626.xsd#fn_Amazon.comInc.Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NameOfMajorCustomerDomain_019ebe77-3cfe-7863-a62c-d1a147fb714d" xlink:to="loc_fn_Amazon.comInc.Member_019f92f7-b4a9-71ef-afdb-1c705ac65f61" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskPercentage1_019ebe77-3cfe-7658-b610-c136db14a414" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskPercentage1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EntityWideRevenueMajorCustomerLineItems_019ebe77-3cfe-7d9a-97c1-1cbbac8947b2" xlink:to="loc_us-gaap_ConcentrationRiskPercentage1_019ebe77-3cfe-7658-b610-c136db14a414" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/BusinesssegmentsandgeographicinformationScheduleofAccountsReceivablefromIndividualCustomersRepresentingTenPercentorMoreofAccountsReceivableDetails" xlink:type="simple" xlink:href="fn-20260626.xsd#BusinesssegmentsandgeographicinformationScheduleofAccountsReceivablefromIndividualCustomersRepresentingTenPercentorMoreofAccountsReceivableDetails"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/BusinesssegmentsandgeographicinformationScheduleofAccountsReceivablefromIndividualCustomersRepresentingTenPercentorMoreofAccountsReceivableDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_fn_ScheduleOfEntityWideAccountsReceivableByMajorCustomersByReportingSegmentsLineItems_019ebe77-3cfe-7465-adfa-3e9b58b9d23e" xlink:href="fn-20260626.xsd#fn_ScheduleOfEntityWideAccountsReceivableByMajorCustomersByReportingSegmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_ScheduleOfEntityWideAccountsReceivableByMajorCustomersByReportingSegmentsTable_019ebe77-3cfe-7a66-94a3-c19492bfda68" xlink:href="fn-20260626.xsd#fn_ScheduleOfEntityWideAccountsReceivableByMajorCustomersByReportingSegmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_fn_ScheduleOfEntityWideAccountsReceivableByMajorCustomersByReportingSegmentsLineItems_019ebe77-3cfe-7465-adfa-3e9b58b9d23e" xlink:to="loc_fn_ScheduleOfEntityWideAccountsReceivableByMajorCustomersByReportingSegmentsTable_019ebe77-3cfe-7a66-94a3-c19492bfda68" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_019ebe77-3cfe-7ca6-aefd-ae522c1b8d5f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskByBenchmarkAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_fn_ScheduleOfEntityWideAccountsReceivableByMajorCustomersByReportingSegmentsTable_019ebe77-3cfe-7a66-94a3-c19492bfda68" xlink:to="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_019ebe77-3cfe-7ca6-aefd-ae522c1b8d5f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019ebe77-3cfe-7ca6-aefd-ae522c1b8d5f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_019ebe77-3cfe-7ca6-aefd-ae522c1b8d5f" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019ebe77-3cfe-7ca6-aefd-ae522c1b8d5f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019ebe77-3cfe-79ac-99ca-5e359c7e0c4c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_019ebe77-3cfe-7ca6-aefd-ae522c1b8d5f" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019ebe77-3cfe-79ac-99ca-5e359c7e0c4c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsReceivableMember_019ebe77-3cfe-75d1-87f1-e1ec371557df" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsReceivableMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019ebe77-3cfe-79ac-99ca-5e359c7e0c4c" xlink:to="loc_us-gaap_AccountsReceivableMember_019ebe77-3cfe-75d1-87f1-e1ec371557df" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByTypeAxis_019ebe77-3cfe-786b-9102-0a046b3aeecb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskByTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_fn_ScheduleOfEntityWideAccountsReceivableByMajorCustomersByReportingSegmentsTable_019ebe77-3cfe-7a66-94a3-c19492bfda68" xlink:to="loc_us-gaap_ConcentrationRiskByTypeAxis_019ebe77-3cfe-786b-9102-0a046b3aeecb" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_019ebe77-3cfe-786b-9102-0a046b3aeecb_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_019ebe77-3cfe-786b-9102-0a046b3aeecb" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_019ebe77-3cfe-786b-9102-0a046b3aeecb_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_019ebe77-3cfe-740d-a2e8-987d0a5a45e0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_019ebe77-3cfe-786b-9102-0a046b3aeecb" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_019ebe77-3cfe-740d-a2e8-987d0a5a45e0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CustomerConcentrationRiskMember_019ebe77-3cfe-73a3-a917-b3d5c145ac11" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CustomerConcentrationRiskMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskTypeDomain_019ebe77-3cfe-740d-a2e8-987d0a5a45e0" xlink:to="loc_us-gaap_CustomerConcentrationRiskMember_019ebe77-3cfe-73a3-a917-b3d5c145ac11" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MajorCustomersAxis_019ebe77-3cfe-7ee9-bf9b-db02df4e79f0" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MajorCustomersAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_fn_ScheduleOfEntityWideAccountsReceivableByMajorCustomersByReportingSegmentsTable_019ebe77-3cfe-7a66-94a3-c19492bfda68" xlink:to="loc_srt_MajorCustomersAxis_019ebe77-3cfe-7ee9-bf9b-db02df4e79f0" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_NameOfMajorCustomerDomain_019ebe77-3cfe-7ee9-bf9b-db02df4e79f0_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_NameOfMajorCustomerDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_MajorCustomersAxis_019ebe77-3cfe-7ee9-bf9b-db02df4e79f0" xlink:to="loc_srt_NameOfMajorCustomerDomain_019ebe77-3cfe-7ee9-bf9b-db02df4e79f0_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_NameOfMajorCustomerDomain_019ebe77-3cfe-762a-a5b5-0707297ffc71" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_NameOfMajorCustomerDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_MajorCustomersAxis_019ebe77-3cfe-7ee9-bf9b-db02df4e79f0" xlink:to="loc_srt_NameOfMajorCustomerDomain_019ebe77-3cfe-762a-a5b5-0707297ffc71" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_CiscoSystemsIncMember_019ebe77-3cfe-78e6-b637-052835605a1e" xlink:href="fn-20260626.xsd#fn_CiscoSystemsIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NameOfMajorCustomerDomain_019ebe77-3cfe-762a-a5b5-0707297ffc71" xlink:to="loc_fn_CiscoSystemsIncMember_019ebe77-3cfe-78e6-b637-052835605a1e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_NokiaCorporationMember_019ebe77-3cfe-74d1-88f6-5abdc1ff847a" xlink:href="fn-20260626.xsd#fn_NokiaCorporationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NameOfMajorCustomerDomain_019ebe77-3cfe-762a-a5b5-0707297ffc71" xlink:to="loc_fn_NokiaCorporationMember_019ebe77-3cfe-74d1-88f6-5abdc1ff847a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_Amazon.comInc.Member_019f92f8-904f-735c-8f8b-f70ff78c93a6" xlink:href="fn-20260626.xsd#fn_Amazon.comInc.Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NameOfMajorCustomerDomain_019ebe77-3cfe-762a-a5b5-0707297ffc71" xlink:to="loc_fn_Amazon.comInc.Member_019f92f8-904f-735c-8f8b-f70ff78c93a6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_NvidiaCorporationMember_019ebe77-3cfe-77d3-a42c-4e5c0a11dc22" xlink:href="fn-20260626.xsd#fn_NvidiaCorporationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NameOfMajorCustomerDomain_019ebe77-3cfe-762a-a5b5-0707297ffc71" xlink:to="loc_fn_NvidiaCorporationMember_019ebe77-3cfe-77d3-a42c-4e5c0a11dc22" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskPercentage1_019ebe77-3cfe-7723-8d08-870e00eefa9e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskPercentage1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_fn_ScheduleOfEntityWideAccountsReceivableByMajorCustomersByReportingSegmentsLineItems_019ebe77-3cfe-7465-adfa-3e9b58b9d23e" xlink:to="loc_us-gaap_ConcentrationRiskPercentage1_019ebe77-3cfe-7723-8d08-870e00eefa9e" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/FinancialinstrumentsDetails" xlink:type="simple" xlink:href="fn-20260626.xsd#FinancialinstrumentsDetails"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/FinancialinstrumentsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLineItems_019ebe77-3cfe-7b33-8026-b1b47c5a5a8e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeTable_019ebe77-3cfe-7b48-9ef0-46b3c8f55164" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeLineItems_019ebe77-3cfe-7b33-8026-b1b47c5a5a8e" xlink:to="loc_us-gaap_DerivativeTable_019ebe77-3cfe-7b48-9ef0-46b3c8f55164" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_019ebe77-3cfe-7d55-b244-832cf556a0ab" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_019ebe77-3cfe-7b48-9ef0-46b3c8f55164" xlink:to="loc_srt_RangeAxis_019ebe77-3cfe-7d55-b244-832cf556a0ab" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019ebe77-3cfe-7d55-b244-832cf556a0ab_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_019ebe77-3cfe-7d55-b244-832cf556a0ab" xlink:to="loc_srt_RangeMember_019ebe77-3cfe-7d55-b244-832cf556a0ab_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019ebe77-3cfe-7062-b8ee-6044887b59f6" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_019ebe77-3cfe-7d55-b244-832cf556a0ab" xlink:to="loc_srt_RangeMember_019ebe77-3cfe-7062-b8ee-6044887b59f6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_019ebe77-3cfe-763e-bff0-1d930759dca0" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019ebe77-3cfe-7062-b8ee-6044887b59f6" xlink:to="loc_srt_MaximumMember_019ebe77-3cfe-763e-bff0-1d930759dca0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_019ebe77-3cfe-7b18-8a34-9c3c1910620c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_019ebe77-3cfe-7b48-9ef0-46b3c8f55164" xlink:to="loc_us-gaap_FinancialInstrumentAxis_019ebe77-3cfe-7b18-8a34-9c3c1910620c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019ebe77-3cfe-7b18-8a34-9c3c1910620c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019ebe77-3cfe-7b18-8a34-9c3c1910620c" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019ebe77-3cfe-7b18-8a34-9c3c1910620c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019ebe77-3cfe-715e-87a0-df918dd5136e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019ebe77-3cfe-7b18-8a34-9c3c1910620c" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019ebe77-3cfe-715e-87a0-df918dd5136e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignExchangeForwardMember_019ebe77-3cfe-752a-a183-ad441fa44896" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignExchangeForwardMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019ebe77-3cfe-715e-87a0-df918dd5136e" xlink:to="loc_us-gaap_ForeignExchangeForwardMember_019ebe77-3cfe-752a-a183-ad441fa44896" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeTermOfContract_019ebe77-3cfe-7532-8de5-a18f8f1a9e19" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeTermOfContract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_019ebe77-3cfe-7b33-8026-b1b47c5a5a8e" xlink:to="loc_us-gaap_DerivativeTermOfContract_019ebe77-3cfe-7532-8de5-a18f8f1a9e19" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.fabrinet.com/role/SubsequentEventDetails" xlink:type="simple" xlink:href="fn-20260626.xsd#SubsequentEventDetails"/>
  <link:definitionLink xlink:role="http://www.fabrinet.com/role/SubsequentEventDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventLineItems_019ebe77-3cfe-7766-b0a0-91d51b578600" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTable_019ebe77-3cfe-7ded-931f-a595bbefef27" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SubsequentEventLineItems_019ebe77-3cfe-7766-b0a0-91d51b578600" xlink:to="loc_us-gaap_SubsequentEventTable_019ebe77-3cfe-7ded-931f-a595bbefef27" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeAxis_019ebe77-3cfe-709e-b4d7-69e130dd7396" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsequentEventTable_019ebe77-3cfe-7ded-931f-a595bbefef27" xlink:to="loc_us-gaap_SubsequentEventTypeAxis_019ebe77-3cfe-709e-b4d7-69e130dd7396" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_019ebe77-3cfe-709e-b4d7-69e130dd7396_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_019ebe77-3cfe-709e-b4d7-69e130dd7396" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_019ebe77-3cfe-709e-b4d7-69e130dd7396_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_019ebe77-3cfe-7074-b703-316561fc2d4c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_019ebe77-3cfe-709e-b4d7-69e130dd7396" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_019ebe77-3cfe-7074-b703-316561fc2d4c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventMember_019ebe77-3cfe-7598-b036-fa80cfb5ae60" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventTypeDomain_019ebe77-3cfe-7074-b703-316561fc2d4c" xlink:to="loc_us-gaap_SubsequentEventMember_019ebe77-3cfe-7598-b036-fa80cfb5ae60" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_019fc71d-ae26-7620-82bd-81ffba9f67a0" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsequentEventTable_019ebe77-3cfe-7ded-931f-a595bbefef27" xlink:to="loc_srt_StatementGeographicalAxis_019fc71d-ae26-7620-82bd-81ffba9f67a0" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_019fc71d-ae26-7620-82bd-81ffba9f67a0_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_019fc71d-ae26-7620-82bd-81ffba9f67a0" xlink:to="loc_srt_SegmentGeographicalDomain_019fc71d-ae26-7620-82bd-81ffba9f67a0_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_019fc71d-ae26-7f46-8f34-6387d8b0628f" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_019fc71d-ae26-7620-82bd-81ffba9f67a0" xlink:to="loc_srt_SegmentGeographicalDomain_019fc71d-ae26-7f46-8f34-6387d8b0628f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_US_019fc71d-d54d-74b2-9913-8555f39ebaa1" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_US"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_019fc71d-ae26-7f46-8f34-6387d8b0628f" xlink:to="loc_country_US_019fc71d-d54d-74b2-9913-8555f39ebaa1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetAcquisitionAxis_019fcffb-c379-7d01-a9b4-dd2f8bd0d19d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsequentEventTable_019ebe77-3cfe-7ded-931f-a595bbefef27" xlink:to="loc_us-gaap_AssetAcquisitionAxis_019fcffb-c379-7d01-a9b4-dd2f8bd0d19d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetAcquisitionDomain_019fcffb-c379-7d01-a9b4-dd2f8bd0d19d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetAcquisitionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AssetAcquisitionAxis_019fcffb-c379-7d01-a9b4-dd2f8bd0d19d" xlink:to="loc_us-gaap_AssetAcquisitionDomain_019fcffb-c379-7d01-a9b4-dd2f8bd0d19d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetAcquisitionDomain_019fcffb-c379-75b5-aff4-abd5f8246278" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetAcquisitionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AssetAcquisitionAxis_019fcffb-c379-7d01-a9b4-dd2f8bd0d19d" xlink:to="loc_us-gaap_AssetAcquisitionDomain_019fcffb-c379-75b5-aff4-abd5f8246278" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_fn_ManfacturingFacilityMember_019fcffc-1680-7436-abe1-1f47ef4ef437" xlink:href="fn-20260626.xsd#fn_ManfacturingFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetAcquisitionDomain_019fcffb-c379-75b5-aff4-abd5f8246278" xlink:to="loc_fn_ManfacturingFacilityMember_019fcffc-1680-7436-abe1-1f47ef4ef437" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetAcquisitionConsiderationTransferred_019fcffb-10a3-76ed-a83a-ffc37d2585ec" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetAcquisitionConsiderationTransferred"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventLineItems_019ebe77-3cfe-7766-b0a0-91d51b578600" xlink:to="loc_us-gaap_AssetAcquisitionConsiderationTransferred_019fcffb-10a3-76ed-a83a-ffc37d2585ec" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://fasb.org/srt/role/srt-eedm/ExtensibleEnumerationLists" xlink:type="simple" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-roles-2026.xsd#eedm1"/>
  <link:definitionLink xlink:role="http://fasb.org/srt/role/srt-eedm/ExtensibleEnumerationLists" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxAuthorityDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxAuthorityDomain"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_TH" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_TH"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxAuthorityDomain" xlink:to="loc_country_TH" xlink:type="arc" order="141"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesCurrentAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesCurrentAbstract"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccruedLiabilitiesCurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccruedLiabilitiesCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract" xlink:to="loc_us-gaap_AccruedLiabilitiesCurrent" xlink:type="arc" order="41"/>
  </link:definitionLink>
</link:linkbase>
