Definition of agonist in English:

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Pronunciation: /ˈaɡənɪst/


1 Biochemistry A substance which initiates a physiological response when combined with a receptor. Compare with antagonist.
Example sentences
  • They may mimic naturally occurring steroids, act as hormone receptor agonists or antagonists or alter the enzymes responsible for hormone synthesis and degradation.
  • Medications that can reduce androgen levels include estrogen, gonadotropin-releasing hormone agonists, and glucocorticoids.
  • These observations provide support for the model that glucose and structurally related sugars are agonists of the Gpr1 receptor.
2 Anatomy A muscle whose contraction moves a part of the body directly: [as modifier]: there is a failure to select the right agonist muscles Compare with antagonist.
More example sentences
  • In addition, we believe that the agonist / antagonist muscle ratios are important values when considering how the scapula provides stability, mobility, and symptom-free function.
  • The agonist and antagonist muscles work in concert to create muscular balance in the human body.
  • It's a matter of muscle aesthetics: The upper arm looks best when both its opposing muscle groups, the agonists and antagonists - that's bis and tris to you - carry a complementary amount of muscle.
3 another term for protagonist.
Example sentences
  • But now, replying to Harapha’s taunts with a startling invitation to combat, Samson is confident as the agonist was never before depicted.
  • To every agonist, there is an antagonist.



Example sentences
  • Studies have clearly demonstrated that key therapies in the acute attack of migraine share the common pharmacologic activity of serotonin receptor agonism.
  • Rather, all known abused drugs affect a limited number of neurotransmitters by agonism or antagonism of a specific receptor site.
  • An agonist is described as a drug that binds to and activates receptors; the possibility of spontaneous receptor activity and therefore of inverse agonism is not mentioned.


Early 20th century: from Greek agōnistēs 'contestant' (a sense reflected in English in the early 17th century), from agōn 'contest'.

Words that rhyme with agonist

antagonist, protagonist

For editors and proofreaders

Line breaks: agon|ist

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