agonist has definitions from the fields of anatomy,zoology,pharmacology,writing
1
[ noun ] (biochemistry) a drug that can combine with a receptor on a cell to produce a physiological reaction

Related terms

drug biochemistry

2
[ noun ] someone involved in a contest or battle (as in an agon)

Related terms

adversary contestant

3
[ noun ] (writing) the principal character in a work of fiction

Synonyms

protagonist

4
[ noun ] (anatomy,zoology) a muscle that contracts while another relaxes

Examples

"when bending the elbow the biceps are the agonist"

Related terms

antagonistic_muscle

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