1. (v. t.) To assert the contrary of; to oppose in words; to take issue with; to gainsay; to deny the truth of, as of a statement or a speaker; to impugn.

2. (v. t.) To be contrary to; to oppose; to resist.

3. (v. i.) To oppose in words; to gainsay; to deny, or assert the contrary of, something.

abjure abrogate agree to disagree annul answer answer conclusively antagonize argue down assert the contrary be antipathetic be at cross-purposes be contrary to be inimical be opposed to beat against belie break break off brush aside call into question challenge chuck chuck out clash collide conflict conflict with confound confute contemn contest contrapose contrast with contravene controvert counter counteract counterattack counterbalance countercheck counterpoise counterpose countervail counterwork cross crush decline defeat demolish deny despise differ disaccord disaffirm disagree disallow disapprove disavow discard disclaim discount disdain dismiss disown dispose of disprove dispute disregard dissent except exclude falsify finish floor forbid forswear gainsay garble go against go counter to ignore impugn interfere with jangle jar join issue upon jostle juxtapose in opposition lock horns meet head-on militate against mismatch mismate negate negative nonplus not accept not admit nullify object offset oppose oppugn overthrow overturn overwhelm parry pass by pass up play at cross-purposes push aside put to silence rebuff rebut recant reduce to silence refuse refuse to admit refuse to consider refute reject renounce repel repudiate repulse resist retract reverse revoke run against run counter to scout set off settle shove away shut up silence smash all opposition spurn squash squelch subvert swim upstream take back take issue with throw away throw out traverse turn away turn out undermine upset vary waive work against