from The American Heritage® Dictionary of the English Language, 4th Edition

  • n. One involved in a struggle or competition.
  • n. Physiology A contracting muscle that is resisted or counteracted by another muscle, the antagonist.
  • n. Biochemistry A drug or other chemical that can combine with a receptor on a cell to produce a physiologic reaction typical of a naturally occurring substance.

from Wiktionary, Creative Commons Attribution/Share-Alike License

  • n. Someone involved in a contest or battle (as in an agon).
  • n. The muscle that contracts while the other relaxes.
  • n. A molecule that can combine with a receptor on a cell to produce a physiological reaction.

from the GNU version of the Collaborative International Dictionary of English

  • n. One who contends for the prize in public games.

from The Century Dictionary and Cyclopedia

  • n. One who contends for the prize in public games; a combatant; a champion; a dramatic actor. Also called agonister.
  • n. [capitalized] One of a violent party of Donatists in northern Africa in the fourth century.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • n. a muscle that contracts while another relaxes
  • n. someone involved in a contest or battle (as in an agon)
  • n. the principal character in a work of fiction
  • n. (biochemistry) a drug that can combine with a receptor on a cell to produce a physiological reaction


Late Latin agōnista, contender, from Greek agōnistēs, from agōn, contest; see agony.
(American Heritage® Dictionary of the English Language, Fourth Edition)
From Ancient Greek ἀγωνιστής (agōnistēs, "combatant, champion") (Wiktionary)


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