'ancestry-related' is a Modern English compound formed from the noun 'ancestry' and the past-participle adjective 'related'. 'Ancestry' originates from Middle English 'ancestrie' (from Old French and ultimately from Latin roots related to 'ancestor'), where the element 'ancestor' referred to 'a predecessor in the family line'. 'Related' comes from the verb 'relate', from Latin 'referre/relatus' via Old French, where roots conveyed 'to bring back' or 'to refer'.

'Ancestry' developed in Middle English from words like 'ancestrie' derived from Old French 'ancestre'/'ancêtre' (meaning 'ancestor'), itself from Latin forms referring to predecessors; the English noun eventually took the -y suffix to form 'ancestry'. 'Related' is the past participle of 'relate', which passed into English from Old French/Latin participial forms (relatus) and came to be used adjectivally. The compound 'ancestry-related' is a recent Modern English formation combining these elements to mean 'connected with ancestry'.

Initially, component words referred specifically to 'ancestors' and to 'being connected' respectively; combined in Modern English they now specifically denote something 'connected to or concerning one's ancestry'.