"one who yields in combat, one who begs for mercy, one who admits defeat," early 15c., hence "coward, faint-hearted wretch;" from recreant (adj.) and from Old French recreant as a noun, "one who acknowledges defeat, a craven, coward, renegade, traitor, wretch." In English, the sense of "apostate, deserter, villain" is from 1560s.
"a repelling; a check, a defeat; peremptory denial or refusal," 1610s, from rebuff (v.), or from French rebuffe or Italian ribuffo.
c. 1200, discomfiten, "to undo in battle, defeat, overthrow," from Anglo-French descomfiter, Old French desconfire "to defeat, destroy," from des- "not" (see dis-) + confire "make, prepare, accomplish," from Latin conficere "to prepare," from com- "with" (see com-) + combining form of facere "to make, to do" (from PIE root *dhe- "to set, put").
General sense of "defeat or overthrow the plans or purposes of" is from late 14c. Weaker sense of "disconcert" is first recorded 1520s in English, probably by confusion with discomfort. Related: Discomfited; discomfiting.
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 French vainquiss-, present stem of vainquir "conquer," from Old French vainkir, alteration of veintre. Related: Vanquished; vanquishing.
late 14c., "having corners," past-participle adjective from corner (v.). Figurative sense "forced or driven into a position where surrender or defeat is inevitable" is from 1824.