[Nouns] confutation, refutation; answer, complete answer; disproof, conviction, redargution, invalidation; exposure, exposition; clincher; retort; reductio ad absurdum; knock down argument, tu quoque argument; sockdolager [U.S.].
[Verbs] confute, refute, disprove; parry, negative, rebut, redargue, expose, show the fallacy of, defeat; demolish, break (destroy) [more]; overthrow, overturn scatter to the winds, explode, invalidate; silence; put to silence, reduce to silence; clinch an argument, clinch a question; give one a setdown, stop the mouth, shut up; have, have on the hip.
not leave a leg to stand on, cut the ground from under one's feet.
be confuted; fail; expose one's weak point, show one's weak point.
condemned on one's own showing, condemned out of one's own mouth.