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 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, "Know Your Uterus," 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, "Uterine Fibroids Can Wreak Reproductive Havoc. What Are They?," 17 Apr. 2020 Throughout treatment, participants are actively discouraged, if not outright banned from, using opioid agonists that could aid their recovery. Emma Yasinski,, "Doctors and nurses with addictions often denied a crucial recovery option," 30 Sep. 2019 Wait until the hirsute, halting ant-agonists actually appear. Elizabeth Horkley, Quartz, "Our obsession with insects in horror films says a lot about our fear of destroying the planet," 30 Oct. 2019 That is a remarkable achievement, but not one that inspires the kind of hero-worship that accompanies larger-than-life founders and agonists on the model of Steve Jobs. Kevin D. Williamson, National Review, "Don’t Run a Government Like a Business," 15 Oct. 2019 The drugs used can include luteinizing-hormone-releasing hormone (LHRH) agonists, which work to turn off the ovaries’ production of estrogen (this hormone can stoke cancer development). Korin Miller, SELF, "What Are My Options for Ovarian Cancer Treatment?," 13 Dec. 2018 Chances are that your bacon this morning came from pork fed with ractopamine, a beta-agonist that bulks up the pig but can adversely affect the human cardiovascular system and even cause chromosomal abnormalities. Eugenia Bone, WSJ, "‘The Poison Squad’ Review: Ever Wonder What’s In It?," 27 Sep. 2018 GnRH agonists suppress ovulation and essentially induce premature menopause. Zahra Barnes, SELF, "11 Symptoms of Premenstrual Dysphoric Disorder You Shouldn’t Ignore," 6 Feb. 2018

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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Time Traveler for agonist

Time Traveler

The first known use of agonist was in 1658

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Statistics for agonist

Last Updated

24 May 2020

Cite this Entry

“Agonist.” Dictionary, Merriam-Webster, Accessed 6 Jul. 2020.

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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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