counteract

verb

coun·ter·act ˌkau̇n-tər-ˈakt

counteracted; counteracting; counteracts

Synonyms of counteract

: to make ineffective or restrain or neutralize the usually ill effects of by means of an opposite force, action, or influence

a drug used to counteract fatigue

counteraction

ˌkau̇n-tər-ˈak-shən

noun

counteractive

ˌkau̇n-tər-ˈak-tiv

adjective

Examples of counteract in a Sentence

The drug will counteract the poison. this medication will counteract the symptoms but it won't kill the infection

Recent Examples on the Web

Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.

Ferroni said that's likely because the weight of active capital in the market is counteracting and potentially working as a stronger force than that ongoing volatility. — Diana Olick, CNBC, 25 Aug. 2026 To counteract this, daily calf stretches are recommended to decrease strain and tension along the musculotendinous junction of the Achilles tendon. — Karla Rodriguez, Footwear News, 24 Aug. 2026 Perhaps the arrival of Hollywood’s deep pockets, and their promise not to be so AI-focused, will counteract that. — Michael Schneider, Variety, 21 Aug. 2026 While salicylic acid has a reputation for drying out skin, the triple ceramide complex in this cream counteracts that by drenching skin in long-lasting moisture—up to a full day—after application. — Mary Honkus, Glamour, 18 Aug. 2026 See All Example Sentences for counteract

Word History

First Known Use

1655, in the meaning defined above

Time Traveler

The first known use of counteract was in 1655

See more words from the same year

Cite this Entry

Style

“Counteract.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/counteract. Accessed 1 Sep. 2026.

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Kids Definition

counteract

verb

coun·ter·act ˌkau̇nt-ə-ˈrakt

: to lessen the force, action, or influence of : offset

a drug that counteracts a poison

counteraction

-ˈrak-shən

noun

Medical Definition

counteract

transitive verb

coun·ter·act ˌkau̇nt-ə-ˈrakt

: to make ineffective or restrain or neutralize the usually ill effects of by an opposite force

vitamin K counteracts the effects of warfarin

counteraction

-ˈrak-shən

noun

counteract

verb

Synonyms of counteract

Examples of counteract in a Sentence

Word History

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Cite this Entry

Kids Definition

Medical Definition

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counteract

verb

Synonyms of counteract

Examples of counteract in a Sentence

Word History

Rhymes for counteract

Browse Nearby Words

Cite this Entry

Kids Definition

Medical Definition

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