antagonist Meaning, Definition & Usage

noun someone who offers opposition
resister; opposer; adversary; opponent.
noun a muscle that relaxes while another contracts
- when bending the elbow the triceps are the antagonist
noun a drug that neutralizes or counteracts the effects of another drug

L. antagonista, Gr. against + combatant, champion, fr. : cf. F. antagoniste. See Antagonism.

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.
(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.
(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.