agonist
noun
ag·o·nist
ˈa-gə-nist 
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
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In their study, nine patients had succumbed to potentially blinding conditions, as a result of damage to the optic nerve, while taking common GLP-1 agonist drugs such as semaglutide and tirzepatide.
—
New Atlas, 6 Feb. 2025
Weight-loss medications called glucagon-like peptide-1 (GLP-1) receptor agonists include Ozempic, Mounjaro, Wegovy and Zepbound—and they can be prescribed for obesity or type 2 diabetes.
—Justin Gest, Newsweek, 20 Jan. 2025
Glucagon-like peptide-1 (GLP-1) receptor agonists help control blood sugar and support weight loss by reducing appetite and slowing digestion.
—Brandi Jones, Msn-Ed, Health, 14 Dec. 2024
Working as a long-acting full opioid agonist, methadone reduces opioid craving and withdrawal.
—Alyssa Goldberg, USA TODAY, 13 Jan. 2025
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New Atlas, 6 Feb. 2025
Weight-loss medications called glucagon-like peptide-1 (GLP-1) receptor agonists include Ozempic, Mounjaro, Wegovy and Zepbound—and they can be prescribed for obesity or type 2 diabetes.
—Justin Gest, Newsweek, 20 Jan. 2025
Glucagon-like peptide-1 (GLP-1) receptor agonists help control blood sugar and support weight loss by reducing appetite and slowing digestion.
—Brandi Jones, Msn-Ed, Health, 14 Dec. 2024
Working as a long-acting full opioid agonist, methadone reduces opioid craving and withdrawal.
—Alyssa Goldberg, USA TODAY, 13 Jan. 2025
See all Example Sentences for agonist
Dictionary Entries Near agonist
Cite this Entry
“Agonist.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/agonist. Accessed 16 Feb. 2025.
Copy CitationMedical Definition
agonist
noun
ag·o·nist
ˈag-ə-nəst
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 22
: 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
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