coun·​ter·​act | \ˌkau̇n-tər-ˈakt \
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 \ 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

The pair also orient the spacecraft to take advantages of the pressure generated by solar radiation, which can counteract some of the unwanted motion, Young says. Joe Pappalardo, Popular Mechanics, "How a Small CubeSat Became the Unlikely Hero of the InSight Landing," 29 Nov. 2018 There are places in Washington state and elsewhere the land is uplifting and that will counteract absolute sea level change. Phuong Le, The Seattle Times, "Sea level in Seattle could rise 3 feet by 2100 on global warming, report says," 30 July 2018 But facial recognition technology is beginning to pose a major privacy threat, which has led researchers to explore ways to counteract it. Jeff John Roberts, Fortune, "Here's a New Way to Trick Facial Recognition," 13 June 2018 But instead, let’s counteract them with our actions. Brittany Packnett, The Cut, "Stacey Abrams’s Win Is Just the Beginning," 23 May 2018 The green moisturizer is super soothing and works to counteract redness—after a month, the difference is noticeable. Lindsay Schallon, Glamour, "The It Cosmetics Foundation I Tell Everyone About Is 25 Percent Off," 2 Nov. 2018 This is an important point that may serve to counteract the opportunistic narrative that Republicans are pushing in order to discredit Dr. Ford. Cady Drell, Marie Claire, "9 Powerful Quotes from Christine Blasey Ford's Hearing," 27 Sep. 2018 Cheesy/creamy These types of garnishes will help counteract other acidic or spicy ingredients and add richness. Becky Krystal, The Seattle Times, "Quick and easy garnishes to glam up your plain, boring food," 4 Sep. 2018 Another one — which Voloshin participated in — tried using electrical stimulation for muscles to counteract the weakness that develops. Elizabeth Howell,, "Touring Where the Mars-500 'Astronauts' Pretended to Take a Red Planet Journey," 11 July 2018

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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Last Updated

14 Dec 2018

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 \
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 \

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 \ 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).


a nest or breeding place

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