coun·​ter·​act | \ ˌkau̇n-tər-ˈakt How to pronounce counteract (audio) \
counteracted; counteracting; counteracts

Definition of counteract

transitive verb

: 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

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Other Words from counteract

counteraction \ ˌkau̇n-​tər-​ˈak-​shən How to pronounce counteraction (audio) \ noun
counteractive \ ˌkau̇n-​tər-​ˈak-​tiv How to pronounce counteractive (audio) \ 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

But in some instances, intervention workers have been accused of enabling — or in Vides’ case, belonging to — the very gangs whose influence they were hired to counteract. Matthew Ormseth, Los Angeles Times, "He was paid to keep kids out of gangs. Now, he’s charged in grisly MS-13 killings," 20 Aug. 2019 Fact-checking alone won’t be enough to counteract the online tide of misinformation, says Nimmo. Sara Harrison, WIRED, "Instagram Now Fact-Checks, but Who Will Do the Checking?," 16 Aug. 2019 While less than scientific (and suffering from a definite selection bias), this list of channels provided a hazy window to watch what YouTube’s promises to counteract hate looked like in practice. Casey Newton, The Verge, "It’s time to regulate tech platforms with laws, not fines," 30 July 2019 Their overreach lasted well into the next century, when the American colonists, desperate to combat Parliament’s abuses, petitioned King George III to counteract them. Declan Leary, National Review, "Conservatives Should Not Celebrate Religious Tyranny and Coercion," 19 July 2019 Some fear that small donors, unaided, aren’t enough to counteract the power of big donors or dark-money groups. Eric Lach, The New Yorker, "Why Famous, Powerful Presidential Candidates Are Begging You for Five Dollars," 10 June 2019 However, researchers from Harvard might have found a dietary supplement that can counteract this problem: resveratrol, an antioxidant found in grape skin, blueberries and perhaps most famously, red wine. Fox News, "Red wine could help astronauts stay strong on Mars," 25 July 2019 And also looking at astronaut health, another experiment will look at how microgravity impacts healing and tissue regeneration, allowing scientists to develop better ways of counteracting bone density loss in space. Chabeli Herrera,, "SpaceX plans to launch 5,000 pounds of cargo to ISS tonight. But storms may push it to August," 24 July 2019 Chocolate Chunk Tahini Blondies Active: 25 minutes | Total: 45 minutes Servings: 24 two-inch pieces Tahini gives these blondies a nutty and faintly bitter flavor that counteracts what can otherwise be an overly sweet treat. Becky Krystal, The Denver Post, "The key to these gooey, chocolaty blondies? Open sesame.," 3 June 2019

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

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First Known Use of counteract

1655, in the meaning defined above

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Statistics for counteract

Last Updated

21 Sep 2019

Look-up Popularity

Time Traveler for counteract

The first known use of counteract was in 1655

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More Definitions for counteract



English Language Learners Definition of counteract

: act against (something) : to cause (something) to have less of an effect or to have no effect at all


coun·​ter·​act | \ ˌkau̇n-tər-ˈakt How to pronounce counteract (audio) \
counteracted; counteracting

Kids Definition of counteract

: to make (something) have less of an effect or no effect at all The antidote counteracts the poison.


transitive verb
coun·​ter·​act | \ ˌkau̇nt-ə-ˈrakt How to pronounce counteract (audio) \

Medical Definition of counteract

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

Other Words from counteract

counteraction \ -​ˈrak-​shən How to pronounce counteraction (audio) \ noun

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Comments on counteract

What made you want to look up counteract? Please tell us where you read or heard it (including the quote, if possible).


miscellaneous remnants or debris

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