Antagonist | Definition of antagonist by Merriam-Webster

Full Definition of ANTAGONIST

1

: one that contends with or opposes another : adversary, opponent

2

: an agent of physiological antagonism: as

a : a muscle that contracts with and limits the action of an agonist with which it is paired —called also antagonistic muscle

b : a chemical that acts within the body to reduce the physiological activity of another chemical substance (as an opiate); especially : one that opposes the action on the nervous system of a drug or a substance occurring naturally in the body by combining with and blocking its nervous receptor — compare agonist 2b

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Examples of ANTAGONIST

They are interested in character first, and in Don, a foul-mouthed psychopath with a hair-trigger temper and buried longings for Gal's wife, they have created a truly scary antagonist. —David Ansen, Newsweek, 18 June 2001
In the 1970s researchers discovered that the actions of estrogen and other hormones can be blocked chemically by drugs called hormone antagonists … —David Plotkin, Atlantic, June 1996
If the new comptroller is a true antagonist of the seamy bond market practices he decried in the campaign, why has he installed as his first deputy the public finance director from the Dinkins administration who was Holtzman's accomplice in each of those deals. —Wayne Barrett, Village Voice, March 1994
As in that film, Kopple not only draws an intimate portrait of the protagonists and antagonists in the strike, but also deftly locates the workers' struggle within a broad context of economic and political forces. —Frank Thompson, Film Comment, January/February 1991
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Origin of ANTAGONIST

(see antagonize)

First Known Use: 1575

Related to ANTAGONIST

Synonyms: adversary, enemy, foe, hostile, opponent

Antonyms: amigo, friend

Definition of ANTAGONIST for Kids

: a person who is against something or someone else : opponent

Medical Definition of ANTAGONIST

: an agent that acts in physiological opposition <contact between a tooth and its antagonist in the opposing jaw>: as a : a muscle that contracts with and limits the action of an agonist with which it is paired—called also antagonistic muscle; compare agonist 1, synergist 2 b : a chemical that acts within the body to reduce the physiological activity of another chemical substance (as an opiate); especially : one that opposes the action on the nervous system of a drug or a substance occurring naturally in the body by combining with and blocking its nervous receptor—compare agonist 2

Learn More About ANTAGONIST

Thesaurus: All synonyms and antonyms for "antagonist"

Spanish Central: Spanish translation of "antagonist"

Nglish: Translation of "antagonist" for Spanish speakers

Britannica English: Translation of "antagonist" for Arabic speakers

Britannica.com: Encyclopedia article about "antagonist"

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