pursue: [13] Pursue is first cousin to prosecute. Both go back ultimately to Latin prōsequī ‘follow up, pursue’. This led fairly directly to English prosecute, but it also seems to have had a Vulgar Latin descendant *prōsequere, which passed into English via Old French porsivre and Anglo-Norman pursuer as pursue. => prosecute, sue, suit[pursue etymology, pursue origin, 英语词源]