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


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

But, in general, dermatologists recommend starting with a potentially irritating product (like a retinoid) just two or three days a week for at least two weeks or so to see how your skin reacts. Sarah Jacoby, SELF, "Here’s How to Build Your Tolerance to Irritating Skin-Care Products," 26 Mar. 2019 Very gently bite on your partner's tongue or lip mid-makeout, and see how your boo reacts. Yerin Kim, Seventeen, "11 Types of Kisses to Step Up Your Makeout Game," 9 Jan. 2019 There's no word yet on how her ex-husband, Tarek El Moussa, reacted to the news of the secret ceremony. Alyssa Fiorentino, House Beautiful, "Christina El Moussa Married Ant Anstead In A Secret "Winter Wonderland" Wedding," 23 Dec. 2018 Watch the funny moment for yourself, below: And here's how people are reacting to it: The launch of Together: Our Community Cookbook was a family affair for Markle, whose mother Doria Ragland flew in to show her support. Christopher Rosa, Glamour, "Prince Harry Stealing Snacks at Meghan Markle's Cookbook Launch Is a Whole Mood," 21 Sep. 2018 Shepherd reacted by punching the handcuffed woman once in the face, fracturing the orbit of her right eye. Steve Miletich, The Seattle Times, "Federal judge expands his inquiry into overturning of Seattle police officer’s firing," 11 Dec. 2018 But even if vulnerability to fire isn’t determined by wealth, the ability to react and rebuild is. Gaby Del Valle, Vox, "The fires in California highlight — and worsen — the state’s income divide," 15 Nov. 2018 When those Citi Bike stations first debuted, many reacted with horror. Alexandra Lange, Curbed, "Let’s organize the city outside our front door with as much care as we do our homes," 30 Aug. 2018 Robert Callahan, the head of state government affairs at the Internet Association, a major lobbying group, said in a statement reacting to the law’s passage. David Meyer, Fortune, "'We Look Forward to Improvements.' Big Tech Plans to Fight Back Against California's Sweeping New Data Privacy Law," 2 July 2018

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

15 Apr 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



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

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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

What made you want to look up react? Please tell us where you read or heard it (including the quote, if possible).


an act or instance of returning to life

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