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

Two different types of supplements are glomming onto the popularity of GLP-1 agonist drugs like semaglutide and tirzepatide, which mimic a natural appetite-suppressing, blood-sugar-regulating hormone called glucagon-like peptide-1. —Kate Knibbs, WIRED, 14 Aug. 2024

There are likely well over a billion people worldwide who are medically eligible to take a GLP-1 receptor agonist, according to FDA criteria. —Ross Wollen, EverydayHealth.com, 22 July 2024

Only destroying the hindbrain cells prevented weight loss when mice received a GLP-1 agonist, suggesting this region curtails appetite. —Mitch Leslie, science.org, 10 July 2024

One muscle — known as the agonist — contracts to move a limb and another — known as the antagonist — will lengthen in response. —Lizette Ortega, Washington Post, 1 July 2024

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

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