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 The social media giant is facing growing pressure from advertisers to do more to counteract hate speech. NBC News, "Memorial Day to blame for COVID-19 spike, Trump heads to Arizona and NASCAR drivers stand behind Bubba Wallace," 23 June 2020 To counteract their potential burdens, the NBA, MLB and MLS have pledged to help provide COVID-19 tests or antibody tests for the public. Gabe Lacques, USA TODAY, "As sports return, experts fear leagues will use up scarce COVID-19 testing resources," 13 July 2020 In other words, these dust plumes actually counteract the generation of hurricanes. Matt Simon, Wired, "Why Massive Saharan Dust Plumes Are Blowing Into the US," 25 June 2020 The Chinese Protestant evangelists that sinicized Christianity in the early 1920s and ’30s sought to counteract accusations raised by the anti-Christian movement.... WSJ, "Gospel According to Xi Ignores Other Gospel," 18 June 2020 But the restrictions launched to counteract the disease have also been hugely damaging for the economy and have exacerbated existing inequalities in education and the workplace, as well as between genders, races and socio-economic backgrounds. Ivana Kottasová, CNN, "The US, Brazil and others lifted lockdowns early. These charts show just how deadly that decision was," 3 July 2020 In this way, the Trump campaign using Parler as a way to counteract the increasingly stringent gatekeeping of the mainstream social media platforms is similar to how Clinton used MTV and the Arsenio Hall Show to sidestep the mainstream news media. Philip M. Napoli, Wired, "What Trump's Twitter and Clinton's Sax Have in Common," 2 July 2020 Pilots on a Lion Air flight the day before the crash had done that to counteract an identical failure. Alan Levin,, "Boeing Withheld Data on System Linked to Crashes, Report Says," 1 July 2020 Still, the effect may not be pronounced enough to counteract the difference in view. Popular Science, "Panasonic’s new vlogging camera uses facial recognition tracking to isolate the sound of your voice," 25 June 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

30 Jul 2020

Cite this Entry

“Counteract.” Dictionary, Merriam-Webster, Accessed 10 Aug. 2020.

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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 counteraction (audio) \ noun

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