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

We need prospective studies that stratify GLP-1 agonist outcomes by baseline endogenous hormone levels, something no major clinical trial has done.

From Slate • Mar. 22, 2026

It was among the first to pursue products targeting the GIP hormone, and a dual GLP-1 and GIP agonist.

From The Wall Street Journal • Mar. 19, 2026

For more than two decades, scientists have explored a group of cancer drugs known as CD40 agonist antibodies.

From Science Daily • Mar. 16, 2026

It has been more than 20 years since these dopamine agonist drugs were first found to cause impulsive behaviour.

From BBC • Feb. 13, 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 Rosenfeld, Paul