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 While scientists are still working to understand the phenomenon, the basic gist is that humans react well to human-like figures, but only up to a point. Brigit Katz, Smithsonian, "A Minnesota Museum’s Creepy Doll Contest Is Here to Haunt Your Dreams," 31 Oct. 2019 Other countries react and here’s how India replied The ties between India and Malaysia have come under stress over Kashmir. Niharika Sharma, Quartz India, "As Jammu & Kashmir loses its political status, here’s what the past 80 days have meant for it," 31 Oct. 2019 Instead, check out the following steps for a more effective way to react the situation. Carolyn Twersky, Seventeen, "How to Deal With Bullying," 29 Oct. 2019 Even before the acquisition of female suffrage, men reacted to the entrance of women into politics with wariness and hesitation. Barrett Swanson, Harper's magazine, "Men at Work," 28 Oct. 2019 The response to the apology, however, has been less than enthusiastic, and Twitter was quick to react to what many perceived to be another weak response to a growing PR problem for the franchise. Dan Carson, Houston Chronicle, "Internet reacts to Astros exec's apology for conduct toward female reporters," 22 Oct. 2019 Thereby, the population’s ability to react to the changing environment has eroded. Alicia Prager, Quartz Africa, "The fight against Nigeria’s northeast terrorism is also a battle against climate change," 18 Oct. 2019 In an endearing new video, Drummond shares a glimpse into how Pawhuska residents are reacting to her latest tome. Perri Ormont Blumberg, Southern Living, "Ree Drummond Made the Cutest Video for Her New Cookbook—Starring Pawhuska Residents," 16 Oct. 2019 What might have surprised outsiders, however, was how a pair of tribal nations reacted. Nick Martin, The New Republic, "The Connection Between Pipelines and Sexual Violence," 15 Oct. 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

11 Nov 2019

Time Traveler for react

The first known use of react was in 1644

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More Definitions for react


How to pronounce react (audio)

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

Thesaurus: All synonyms and antonyms for react

Rhyming Dictionary: Words that rhyme with react

Spanish Central: Translation of react

Nglish: Translation of react for Spanish Speakers

Britannica English: Translation of react for Arabic Speakers

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