antagonist, n. [opponent], [foe], [adversary], [assailant], [rival], foeman.
antagonistic, a. [contradictory], [repugnant], [conflicting], renitent, adverse.
antecedence, n. [priority], precedence, anteriority. Antonym: posteriority.
antecedent, a. [anterior], [preceding], [prior], [previous]. Antonym: [posterior].
anterior, a. [prior], [before], [antecedent], [previous].
antetype, n. prototype.
antic, n. [caper], [dido], [trick], [gambol], [prank]; [clown], [zany], harlequin, buffoon.
anticipate, v. [expect], [forestall], preclude, obviate.
anticipation, n. [expectation], preclusion, preoccupation, foretaste, antepast, [forethought].
antidote, n. counterpoison, alexipharmic, alexiteric; [corrective], [remedy], [cure].