vanquishyoudaoicibaDictYouDict
vanquish: [14] Vanquish was adapted from vainquiss-, the stem form of Old French vainquir ‘defeat’. This was derived from vaintre ‘defeat’, a descendant of Latin vincere ‘defeat’ (source also of English convince, invincible [15], victory, etc).
=> convince, invincible, victory
vanquish (v.)youdaoicibaDictYouDict
mid-14c., "to defeat in battle, conquer," from Old French venquis-, extended stem of veintre "to defeat," from Latin vincere "defeat" (see victor). Influenced in Middle English by Middle French vainquiss-, present stem of vainquir "conquer," from Old French vainkir, alteration of veintre. Related: Vanquished; vanquishing.