ag·​o·​nist | \ ˈa-gə-nist How to pronounce agonist (audio) \

Definition of agonist

1 : one that is engaged in a struggle
2 [from antagonist]
a : a muscle that is controlled by the action of an antagonist with which it is paired
b : a chemical substance capable of combining with a specific receptor on a cell and initiating the same reaction or activity typically produced by the binding endogenous substance dopaminergic agonists — compare antagonist sense 2b

Examples of agonist in a Sentence

Recent Examples on the Web Methadone is an opioid agonist that reduces cravings and withdrawal symptoms by activating opioid receptors. Sarah Fielding,, 17 Nov. 2021 The most common treatments for acute migraine include the triptan (selective 5-hydroxytryptamine serotonin receptor agonist) class of medicines. Joshua Cohen, Forbes, 3 Oct. 2021 Opioid agonist therapies, including methadone and suboxone, can also suppress testosterone. Alia E. Dastagir, USA TODAY, 23 July 2021 On Friday, June 4th, the Food and Drug Administration (FDA) approved Novo Nordisk’s obesity drug Wegovy (semaglutide), a glucagon-like peptide 1 receptor agonist, to be injected subcutaneously once-weekly. Joshua Cohen, Forbes, 5 June 2021 Her method is based on a sister surgery called the AMI method, invented at the MIT Media Lab, which reconnects agonist and antagonist muscles in amputees. Globe Staff,, 15 Feb. 2021 Medical treatments can include hormonal therapy delivered via a combination birth control pill, patch or ring; or a progesterone-only pill, injection, implant or I.U.D.; as well as drugs called GnRH agonists and antagonists. Katherine Hobson, New York Times, 18 Apr. 2020 Other types of drugs — such as gonadotropin-releasing hormone agonists — can shrink tumors by decreasing the hormone producing activity of your ovaries, lowering your estrogen levels. Hilda Hutcherson, New York Times, 17 Apr. 2020 Throughout treatment, participants are actively discouraged, if not outright banned from, using opioid agonists that could aid their recovery. Emma Yasinski,, 30 Sep. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'agonist.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of agonist

1658, in the meaning defined at sense 1

History and Etymology for agonist

borrowed from Late Latin agōnista, borrowed from Greek agōnistḗs, from agōnízesthai "to contend, fight" + -istēs -ist entry 1 — more at agonize

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The first known use of agonist was in 1658

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Last Updated

29 Nov 2021

Cite this Entry

“Agonist.” Dictionary, Merriam-Webster, Accessed 30 Nov. 2021.

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More Definitions for agonist


ag·​o·​nist | \ ˈag-ə-nəst How to pronounce agonist (audio) \

Medical Definition of agonist

1 : a muscle that on contracting is automatically checked and controlled by the opposing simultaneous contraction of another muscle

called also agonist muscle, prime mover

— compare antagonist sense a, synergist sense 2
2 : a chemical substance (as a drug) capable of combining with a receptor on a cell and initiating the same reaction or activity typically produced by the binding of an endogenous substance binding of adrenergic agonists — compare antagonist sense b

More from Merriam-Webster on agonist

Nglish: Translation of agonist for Spanish Speakers Encyclopedia article about agonist


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