react

verb
re·​act | \ rē-ˈakt \
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

Synonyms

reply, respond

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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

Emerging-market currencies rallied Thursday, as investors reacted to a dovish pivot from the Federal Reserve. Ira Iosebashvili, WSJ, "Emerging-Market Currencies Rise on Dovish Fed," 31 Jan. 2019 The company’s stock languished through early October, nearly matching its low point from the spring, as investors reacted to the settlement and news of the government’s increased focus on Tesla. Sean O'kane, The Verge, "The Verge 2018 tech report card: Tesla," 29 Dec. 2018 The addicted brain is compulsively seeking the drug that stops painful withdrawal – not reacting to health and safety threats for themselves or anyone else, experts say. Terry Demio, Cincinnati.com, "Living with HIV: Fueled by heroin, HIV makes an alarming resurgence in Cincinnati," 11 July 2018 Most Facebook users reacting to Giddings' post condemned the lawmaker's post. refinery29.com, "GOP State Representative Who Implied She Could Shoot Peaceful Protesters Is Running Unchallenged," 29 June 2018 Ozone is formed when nitrogen and volatile organic compounds, such as paint fumes, react in sunlight. Kate Talerico, The Courier-Journal, "Louisville had worst air quality in country last weekend," 21 June 2018 In other cases, an animal might not be grieving but trying to determine why their companion isn’t reacting. Virginia Morell, Science | AAAS, "Do dolphins feel grief?," 19 June 2018 The setae on crustaceans often act like whiskers, helping the animals detect and react to changes in their environment. Brigit Katz, Smithsonian, "Introducing a Hairy-Footed Shrimp Named After Bilbo Baggins," 13 June 2018 In concert with a team of researchers from the U.S. and Japan, Benner has shown that when sulfur dioxide (likely off-gassed from volcanoes) reacts with formaldehyde, the result is a compound called hydroxymethanesultonate, or HMS for short. Jill Kiedaisch, Popular Mechanics, "Life on Earth May Have Been Born From a Maelstrom of Molten Iron," 15 Jan. 2019

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

18 Feb 2019

Look-up Popularity

Time Traveler for react

The first known use of react was in 1644

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More Definitions for react

react

verb

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

react

verb
re·​act | \ rē-ˈakt \
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 \

Medical Definition of react

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

transitive verb

: to cause to react

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More from Merriam-Webster on react

Rhyming Dictionary: Words that rhyme with react

Thesaurus: All synonyms and antonyms for react

Spanish Central: Translation of react

Nglish: Translation of react for Spanish Speakers

Britannica English: Translation of react for Arabic Speakers

Comments on react

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