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 counteract (audio) \ noun
counteractive \ ˌkau̇n-​tər-​ˈak-​tiv How to pronounce counteract (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 There are two categories of ingredients found in moisturizing skincare products that can help maintain the ideal water content in the outer layer of skin (a.k.a. the stratum corneum) to counteract dryness. Sabina Wizemann, Good Housekeeping, "What You Need to Know About Occlusives in Skincare," 28 Dec. 2020 At this point, Marazuela concludes, dropping evaporation rates can no longer counteract the effects of brine pumping. Ian Morse, Quartz, "Chile’s new constitution could rewrite the story of lithium mining," 22 Dec. 2020 Everyone else should be watched for 15 minutes -- and immunization providers should have medical supplies, such as epinephrine that can counteract allergic reactions, on hand. oregonlive, "COVID-19 vaccines are in Oregon and more are on the way. What you need to know: Q&A," 18 Dec. 2020 Selling ice cream could help counteract the seasonal sales slump. CNN, "This company conquered the ice cream market. Home delivery is the final frontier," 14 Nov. 2020 As a whole, these can be difficult to counteract, but the major platforms have committed to either delete or tag these posts as suspect. Sam Dean, Los Angeles Times, "How Facebook and Twitter plan to handle election day disinformation," 2 Nov. 2020 For the eyes, concentrate on the under eyes and inner corners to effectively counteract dark circles. Lauren Valenti, Vogue, "A Guide to Ageless Makeup for Women Over 50, According to an Industry Veteran," 12 Oct. 2020 In trying to counteract harmful stereotypes, the show has succeeded in doing something altogether stranger: erasing diversity through the act of depicting it. Cheri Lucas Rowlands, Longreads, "Longreads Best of 2020: Arts and Culture," 16 Dec. 2020 Rather than automatically impose tariffs to counteract British divergence, the two sides are negotiating other ways to resolve disputes over state aid and other competition policies. New York Times, "Going ‘the Extra Mile,’ Britain and E.U. Give Brexit Talks More Time," 13 Dec. 2020

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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Time Traveler for counteract

Time Traveler

The first known use of counteract was in 1655

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Statistics for counteract

Last Updated

8 Jan 2021

Cite this Entry

“Counteract.” Dictionary, Merriam-Webster, Accessed 15 Jan. 2021.

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More Definitions for counteract


How to pronounce counteract (audio)

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 counteract (audio) \ noun

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