An*tag"o*nist (&?;), n. [L.
antagonista, Gr. &?;; &?; against + &?; combatant, champion, fr.
&?;: cf. F. antagoniste. See Antagonism.] 1.
One who contends with another, especially in combat; an adversary; an
opponent.
Antagonist of Heaven's Almigthy King.
Milton.
Our antagonists in these controversies.
Hooker.
2. (Anat.) A muscle which acts in opposition
to another; as a flexor, which bends a part, is the
antagonist of an extensor, which extends it.
3. (Med.) A medicine which opposes the
action of another medicine or of a poison when absorbed into the blood or
tissues.
Syn. -- Adversary; enemy; opponent; toe; competitor. See
Adversary.
An*tag"o*nist, a. Antagonistic;
opposing; counteracting; as, antagonist schools of
philosophy.