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

Recent Examples on the Web

One possible explanation is that GLP-1 receptor agonists increase feelings of fullness, which could make alcohol less appealing, Hendershot said. —Dr. Christopher Wachuku, ABC News, 12 Feb. 2025

Medications known as glucagon-like peptide-1 agonists, or GLP-1s, have become very popular as weight loss agents. —Joshua P. Cohen, Forbes, 1 Dec. 2024

Ann Tsung, a NASA flight surgeon, is currently seeking approval to test whether GLP-1 agonists — drugs that have gained widespread attention under names such as Ozempic and Mounjaro as treatments for diabetes and obesity — can treat SANS by lowering intracranial pressure. —Neil Savage, Scientific American, 6 Mar. 2025

Weight-loss brand Atkins, Nestlé, and the nutrition arm of healthcare brand Abbott have created food products designed for GLP-1 agonist users. —Sindhya Valloppillil, Forbes, 26 Feb. 2025

Word History

Etymology

borrowed from Late Latin agōnista, borrowed from Greek agōnistḗs, from agōnízesthai "to contend, fight" + -istēs -ist entry 1 — more at agonize

First Known Use

1658, in the meaning defined at sense 1

Rhymes for agonist

• antagonist
• protagonist

Medical 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 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