Meaning of agonist

ag•o•nist

Pronunciation: (ag'u-nist), [key]
— n.
  1. a person engaged in a contest, conflict, struggle, etc., esp. the protagonist in a literary work.
  2. a person who is torn by inner conflict.
  3. a contracting muscle whose action is opposed by another muscle. Cf. antagonist (def. 3).
  4. a chemical substance capable of activating a receptor to induce a full or partial pharmacological response. Cf. antagonist (def. 5).
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.
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