to conquer or subdue by superior force, as in battle.
2.
to defeat in any contest or conflict; be victorious over: to vanquish one's opponent in an argument.
3.
to overcome or overpower: He vanquished all his fears.
Origin: 1300–50; Middle English vencuschen,venquisshen < Old French vencus past participle and venquis past tense of veintre < Latin vincere to overcome
early 14c., from O.Fr. venquis (past tense), and vencus (p.p.), from veintre "defeat," from L. vincere "defeat" (see victor). Influenced in M.E. by M.Fr. vainquiss-, present stem of vainquir "conquer," from O.Fr. vainkir, alteration of veintre.