re·​act | \ rē-ˈakt How to pronounce react (audio) \
reacted; reacting; reacts

Definition of react

intransitive verb

1 : to exert a reciprocal or counteracting force or influence often used with on or upon
2 : to change in response to a stimulus
3 : to act in opposition to a force or influence usually used with against
4 : to move or tend in a reverse direction
5 : to undergo chemical reaction

transitive verb

: to cause to react

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Synonyms for react


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Examples of react in a Sentence

When I told her what happened, she reacted with anger. I didn't expect him to react that way. The firefighters reacted quickly when they heard the alarm. He reacted badly to the drug.
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Recent Examples on the Web These days usually take place during warm months, when pollutants react with heat and sunlight to create ozone. London Gibson, The Indianapolis Star, 2 June 2021 While top Democratic leaders did not react publicly to the blocking of the Texas bill Monday, House Speaker Nancy Pelosi, D-Calif., and Senate Majority Leader Charles E. Schumer, D-N.Y., have continued to push for passage of the For the People Act. Amy Gardner, Anchorage Daily News, 1 June 2021 The extra space between the alignment of the offensive tackle and LEO means that a tackle’s quick sets take a touch more time to land, thus giving the LEO ample time to react and counter. John Owning, Dallas News, 24 May 2021 So, even if the current inflation surge does prove bigger and more persistent than policymakers expect, the Fed should have plenty of time to react. John Cassidy, The New Yorker, 17 May 2021 Instead, its chief criticism was of governments that had more time to react but failed to. Betsy Mckay, WSJ, 12 May 2021 Home fires can occur day or night, and residents often have little time to react. cleveland, 28 Apr. 2021 Also, in the second half of the season, the pitching rubber will be moved back a foot to 61 feet, 6 inches from home plate, a rule designed to give batters more time to react to pitches. Tom Haudricourt, Milwaukee Journal Sentinel, 14 Apr. 2021 The hacker would still need 36 hours to lock you out of your account, which gives you plenty of time to react. Chris Smith, BGR, 13 Apr. 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'react.' 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 react

1644, in the meaning defined at intransitive sense 1

History and Etymology for react

New Latin reactus, past participle of reagere, from Latin re- + agere to act — more at agent

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Statistics for react

Last Updated

4 Jun 2021

Cite this Entry

“React.” Dictionary, Merriam-Webster, Accessed 14 Jun. 2021.

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More Definitions for react



English Language Learners Definition of react

: to behave or change in a particular way when something happens, is said, etc.
of a chemical substance : to change after coming into contact with another substance
medical : to be affected by a drug, food, etc., in usually a bad way


re·​act | \ rē-ˈakt How to pronounce react (audio) \
reacted; reacting

Kids Definition of react

1 : to act or behave in response to something Firefighters reacted quickly to the situation.
2 : to oppose a force or influence
Hint: In this sense, react is usually used with against. Workers reacted against unfair treatment.
3 : to go through a chemical reaction Acids react with bases to form salt.
re·​act | \ rē-ˈakt How to pronounce react (audio) \

Medical Definition of react

1 : to respond to a stimulus
2 : to undergo chemical reaction

transitive verb

: to cause to react

More from Merriam-Webster on react

Thesaurus: All synonyms and antonyms for react

Nglish: Translation of react for Spanish Speakers

Britannica English: Translation of react for Arabic Speakers


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