Meaning of agonist

Definition of agonist

(noun) the principal character in a work of fiction
someone involved in a contest or battle (as in an agon)
a muscle that contracts while another relaxes; "when bending the elbow the biceps are the agonist"
(biochemistry) a drug that can combine with a receptor on a cell to produce a physiological reaction

Other information on agonist

WIKIPEDIA results for agonist
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