Definition of defeat :
1. An overthrow, as of an army in battle; loss of a battle; repulse suffered; discomfiture; - opposed to victory.
2. An undoing or annulling; destruction.
3. Frustration by rendering null and void, or by prevention of success; as, the defeat of a plan or design.
4. To overcome or vanquish, as an army; to check, disperse, or ruin by victory; to overthrow.
5. To render null and void, as a title; to frustrate, as hope; to deprive, as of an estate.
6. To resist with success; as, to defeat an assault.
7. To undo; to disfigure; to destroy.
surpass, Waterloo, hiding, obliterate, whipping, rebuff, dusting, massacre, castigate, land, belabor, get the better of, baffle, frustration, comedown, bruise, extermination, shoot, ace, overtake, whacking, pour down, belt down, disappointment, toss off, breakdown, subjugate, debacle, tear, lick, withdrawal, conquest, cross, kill, turn thumbs down, destruction, thwart, trim, bolt down, repulse, ambush, thrashing, pound, trouncing, worst, drubbing, count, stymie, thrash, fall, loss, butchery, allow, lacing, scourge, overwhelm, stump, check, switch, get the best, whelm, flog, pop, get over, strike, dud, breakthrough, ruin, have the best, prevail against, stalemate, smite, thwarting, sweep over, blow, vanquishment, chastise, frustrate, upset, black eye, drink down, buck, annihilation, walloping, charge, victory, licking, best, setback, pommel, batter, vote down, shoot down, foiling, slaughter, balk, stamp out, vote out, reverse, success, spank, wipe out, down, cudgel, trimming, knockout, bastinado, trap
defeat (part of speech: verb)
humble, downfall, failure, beating, beat, overcome, crush, rout, conquer, foil, quell, outdo, overturn, overpower, subdue, capture, whip, predominate, vanquish, subject, outplay, trump, overthrow, trounce, checkmate, triumph, master, collapse, win, surmount