coadjutor
Coadjutor (noun) means a person who helps or assists someone else.
Etymology
Came into English from Middle English coadjutowre, from Old French coadjuteur, itself borrowed from Late Latin coadiūtōrem, formed from co- and adiūtor (‘helper’), which comes from adiuvō (‘to help’) plus the agent suffix -tor. By surface analysis it can also be read as co- + adjutor. The French route produced the stress pattern coˈadjutor, used by Samuel Taylor Coleridge, but poets generally, since 1600, have favoured coaˈdjutor, following Latin. No Latin *coadiuvō or *coadiūtō is actually recorded, but modern languages have coined words on those patterns, suggested by coadjutor.