n. 25B6; verb
the army which defeated the Scots : BEAT, conquer, win against, triumph over, get the better of, vanquish; rout, trounce, overcome, overpower, crush, subdue; informal lick, thrash, whip, wipe the floor with, make mincemeat of, clobber, slaughter, demolish, cane; Brit. informal stuff; N. Amer. informal cream, skunk.
these complex plans defeat their purpose : THWART, frustrate, foil, ruin, scotch, debar, snooker, derail; obstruct, impede, hinder, hamper; informal put the kibosh on, put paid to, stymie; Brit. informal scupper, nobble.
the motion was defeated : REJECT, overthrow, throw out, dismiss, outvote, turn down; informal give the thumbs down.
how to make it work defeats me : BAFFLE, perplex, bewilder, mystify, bemuse, confuse, confound, throw; informal beat, flummox, faze, stump, fox.
25B6; noun
a crippling defeat : LOSS, conquest, vanquishment; rout, trouncing; downfall; informal thrashing, hiding, drubbing, licking, pasting, massacre, slaughter.
the defeat of his plans : FAILURE, downfall, collapse, ruin; rejection, frustration, abortion, miscarriage; undoing, reverse.
victory, success.