vanquish (v.) Look up vanquish at Dictionary.com
mid-14c., "to defeat in battle, conquer," from Old French venquis-, extended stem of veintre "to defeat," from Latin vincere "to overcome, conquer" (from nasalized form of PIE root *weik- (3) "to fight, conquer"). Influenced in Middle English by Middle French vainquiss-, present stem of vainquir "conquer," from Old French vainkir, alteration of veintre. Related: Vanquished; vanquishing.