Antagonist

n.	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.
a.	1.	Antagonistic; opposing; counteracting; as, antagonist schools of philosophy.

Noun	1.	antagonist - someone who offers opposition Synonyms: adversary, opposer, resister, opponent Antonyms: agonist - someone involved in a contest or battle (as in an agon)
	2.	antagonist - a muscle that relaxes while another contracts; "when bending the elbow the triceps are the antagonist"
	3.	antagonist - a drug that neutralizes or counteracts the effects of another drug Antonyms: synergist - a drug that augments the activity of another drug

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