antagonist

noun an·tag·o·nist \ an-ˈta-gə-nist \

Definition of antagonist

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

political antagonists

2 :an agent of physiological antagonism: such 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 (such 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

See antagonist defined for English-language learners

See antagonist defined for kids

Examples of antagonist in a Sentence

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
please name the novel's hero and his antagonist
his antagonist in the boxing match

Recent Examples of antagonist from the Web

Churchill’s greatest antagonist in later years was Labour’s minister of health Aneurin Bevan, founder of the National Health Service, who excoriated Churchill at every opportunity.

— richard m. langworth, National Review, "How Would Churchill Tweet?," 12 Aug. 2017
The Mean Girls antagonist, played brilliantly by Rachel McAdams, is one of the greatest characters in film history—

— christopher rosa, Glamour, "This Regina George Doppelgänger Is Stunning Everyone on Twitter," 7 Aug. 2017
A catastrophic explosion has destroyed pretty much everything on the island—including a biology lab—except an enigmatic robot named DOC73R-CY3N53 who ends up being your antagonist.

— theo karasavvas, Ars Technica, "Level up: How video games evolved to solve significant scientific problems," 23 July 2017
Naltrexone, by contrast, is an opioid antagonist, or blocker.

— The Economist, "What would Hippocrates do?Most people addicted to opioids receive no treatment," 13 July 2017
In a new study published in the journal BMJ Open, researchers analyzed data from nearly 350,000 people who were prescribed some type of heartburn drug: either a PPI or H2 receptor antagonist, known as H2 blockers.

— alice park, Time, "These Heartburn Drugs Are Linked to a Higher Risk of Early Death," 5 July 2017
Marvel’s heroes are portrayed as reckless, Captain America comes off as a government tool and Iron Man essentially serves as a second antagonist for Spider-Man (in a Batman and Robin sort of way).

— david frese, kansascity, "‘Spider-Man: Homecoming’ does whatever the other ‘Spider-Mans’ can — only better," 5 July 2017
SHODAN was like a black widow spider, a paralyzing, godlike presence whose seductive brilliance and stammering balefulness made her one of gaming's most memorable antagonists.

— SI.com, "The 15 Most Influential Video Game Characters of All Time," 4 July 2017
The brand Suboxone is a combination of buprenorphine and naloxone, an opioid antagonist.

— nancy coleman, CNN, "Ohio official: Don't send medics for third overdose," 29 June 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'antagonist.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Did You Know?

On the stage or screen, in a story or a novel, the protagonist is the main character and the antagonist is the opposing one. Pro- and ant- usually mark the good and bad characters, but not always; there may occasionally be an evil protagonist and a good antagonist. In the drama of the real world, it's especially hard to sort out which is which, so we usually speak of both parties to a conflict as antagonists. During a strike, for example, representatives of labor and management become antagonists; they often manage to antagonize each other, and the antagonism often remains after the strike is over.

Origin and Etymology of antagonist

see antagonize

NEW! Time Traveler

First Known Use: 1555

See Words from the same year

antagonist Synonyms

Synonyms

adversary, enemy, foe, hostile, opponent

Antonyms

amigo, friend

Related Words

archenemy, archfoe, nemesis; ill-wisher; bane, bête noire; assailant, attacker, combatant, invader; competitor, emulator, rival

Near Antonyms

buddy, chum, compadre, crony, fellow, hail-fellow, hail-fellow-well-met, hearty, hobnobber, mate, musketeer, pal; abettor (also abetter), accomplice, ally, collaborator, colleague, comrade, confederate, friendly, partner; adherent, disciple, follower; backer, benefactor, exponent, supporter, sympathizer, well-wisher

ANTAGONIST Defined for English Language Learners

antagonist

noun

Definition of antagonist for English Language Learners

: a person who opposes another person

ANTAGONIST Defined for Kids

antagonist

noun an·tag·o·nist \ an-ˈta-gə-nəst \

Definition of antagonist for Students

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

Medical Dictionary

antagonist

noun an·tag·o·nist \ -nəst \

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