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