counteract

American  

[koun-ter-akt] / ˌkaʊn tərˈækt /

verb (used with object)

1. to act in opposition to; frustrate by contrary action.

   Synonyms:

   thwart, contravene, counterbalance, neutralize

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counteract British  

/ ˌkaʊntərˈækt /

verb

1. (tr) to oppose, neutralize, or mitigate the effects of by contrary action; check

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Other Word Forms

• counteractant adjective
• counteracter noun
• counteractingly adverb
• counteraction noun
• counteractive adjective
• counteractively adverb
• counteractor noun
• noncounteractive adjective
• uncounteracted adjective

Etymology

Origin of counteract

First recorded in 1670–80; counter- + act

Example Sentences

None of it did much to counteract the sense that life had become too expensive.

From Slate • Mar. 25, 2026

AI’s sycophancy reinforces human confirmation bias, but users can employ tactics to counteract this tendency.

From The Wall Street Journal • Mar. 21, 2026

Announcing its approval, the FCC said the deal would help "counteract the growing imbalance of power" between local broadcast TV stations and the large media firms, including Fox, Disney and Paramount, that dominate programming.

From BBC • Mar. 20, 2026

Former Manchester City goalkeeper Shay Given suggested earlier this season that keeping players up while defending corners could be an effective way to counteract Arsenal's threat.

From BBC • Mar. 11, 2026

By putting two gold-covered plates on a sensitive twist-measuring device, he determined how much force it took to counteract the Casimir force between them.

From "Zero: The Biography of a Dangerous Idea" by Charles Seife

Related Words

• cancel out
• correct
• counterbalance
• halt
• negate
• neutralize
• offset
• prevent
• rectify
• redress
• resist
• thwart