agonist

American  

[ag-uh-nist] / ˈæg ə nɪst /

noun

1. a person engaged in a contest, conflict, struggle, etc., especially the protagonist in a literary work.

2. a person who is torn by inner conflict.

3. Physiology. a contracting muscle whose action is opposed by another muscle.

4. Pharmacology. a chemical substance capable of activating a receptor to induce a full or partial pharmacological response.

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agonist British  

/ ˈæɡənɪst /

noun

1. any muscle that is opposed in action by another muscle Compare antagonist

2. a competitor, as in an agon

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agonist Scientific  

/ ăg′ə-nĭst /

1. A muscle that actively contracts to produce a desired movement.

2. A chemical substance, especially a drug, that can combine with a receptor on a cell to produce a physiologic response.

3. Compare antagonist

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Etymology

Origin of agonist

First recorded in 1620–30; from Late Latin agōnista, from Greek agōnistḗs “contestant,” equivalent to agṓn agon + -istēs -ist

Example Sentences

See Examples For:

agonist

The researchers also tested setmelanotide, an anti-obesity MC4R agonist.

From Science Daily ● Aug. 13, 2026

So did Ozempic and, later, Lilly’s GIP/GLP-1 agonist, which was approved as Mounjaro for Type 2 diabetes in mid-2022 and as Zepbound for weight loss in late 2023.

From MarketWatch ● Aug. 5, 2026

Meanwhile, the march of the GLP-1 agonist wonder drugs continues.

From The Wall Street Journal ● Jun. 21, 2026

He views Lilly’s selective amylin agonist, eloralintide, a once-weekly injectable and potential obesity treatment, as another potential winner, noting its potentially best-in-class tolerability and efficacy.

From Barron's ● Jun. 9, 2026

Sometimes, one glimpses a little too long behind his work not the heroic agonist, but the man who loved to languish in mournful salons, attired in furred dressing gowns.

From Musical Portraits Interpretations of Twenty Modern Composers by Paul Rosenfeld