antagonist

[an-tag-uh-nist]

noun

1. a person who is opposed to, struggles against, or competes with another; opponent; adversary.

   Synonyms: foe, enemy, contestant
   Antonyms: friend, ally

2. the adversary of the hero or protagonist of a drama or other literary work.

   Iago is the antagonist of Othello.

3. Physiology.,  a muscle that acts in opposition to another.

4. Dentistry.,  a tooth in one jaw that articulates during mastication or occlusion with a tooth in the opposing jaw.

5. Pharmacology.,  a drug that counteracts the effects of another drug.

antagonist

/ ænˈtæɡənɪst /

noun

1. an opponent or adversary, as in a contest, drama, sporting event, etc

2. any muscle that opposes the action of another Compare agonist

3. a drug that counteracts the effects of another drug Compare synergist

antagonist

1. A muscle that opposes the action of another muscle, as by relaxing while the other one contracts, thereby producing smooth, coordinated movement.

2. A chemical substance, such as a drug, that interferes with the physiological action of another substance, especially by combining with and blocking its nerve receptor.

3. Compare agonist

Word History and Origins

Origin of antagonist¹

First recorded in 1590–1600; from Late Latin antagōnista, from Greek antagōnistḗs. See antagonize, -ist

Synonym Study

See adversary.

Example Sentences

What doesn’t change with the times is that “It” is synonymous with its star antagonist, Pennywise, the sinister clown that terrorizes Derry.

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The president’s shifting cast of antagonists are many.

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The backlash against the current actions in Portland from obvious antagonists was expected.

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Athena isn’t a particularly intimidating antagonist, given that Julian seems to have forgotten to give her crucial abilities and weapons.

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“Task” has been steadily burning toward this meeting of its two flawed men, neither of whom entirely registers as protagonist or antagonist.

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Related Words

• adversary 
• enemy 
• foe