Origin: 1250–1300; Middle English conquerour < Anglo-French; Old French conquereor, equivalent to conquer-conquer + -eor < Latin -ōr--or1 or -ātōr--ator
c.1300, from Anglo-Fr. conquerour (O.Fr. conquereor), from O.Fr. conquerre (see conquer). Another early form was conquestor. William the Conqueror so called from early 12c. in Anglo-L.: Guillelmus Magus id est conquæstor rex Anglorum.