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 The study also didn't account for how children with disabilities would react to time in green spaces. Gabriela Miranda, USA TODAY, 20 July 2021 The past year has brought enormous stress and loss, and people will process and react differently. Washington Post, 19 July 2021 While Seibert has faced the pressure of an NFL kick, the Bengals have their training-camp practices and three preseason games to see how McPherson will react. Mark Inabinett |, al, 17 July 2021 And so the book, as well as the series, develops into a rather fascinating examination of varying ways humans react to chaotic, frightening situations. David James, Anchorage Daily News, 17 July 2021 When the volcanoes erupt, these phosphides could be thrust into the atmosphere and chemically react with sulfuric acid in the clouds to form phosphine. Katrina Miller, Wired, 14 July 2021 Shifting to the current debate over voting rights, Roberts asked how Lewis would react to the recent DOJ lawsuit brought against Georgia -- Lewis' home state -- due to the state legislature's passing of restrictive voting laws. Sydnie Cobb, ABC News, 13 July 2021 Officials have not provided a date for when the review will be complete but plan to update their incident playbook to more effectively react to extreme heat in the future. oregonlive, 11 July 2021 Those desires have only strengthened with how Calderon saw Roger Penske and Penske Entertainment Corp. react to holding the first Indy 500 since 2000 without a female driver in 2020. Nathan Brown, The Indianapolis Star, 10 July 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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Dictionary Entries Near react



react against

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Statistics for react

Last Updated

22 Jul 2021

Cite this Entry

“React.” Dictionary, Merriam-Webster, Accessed 1 Aug. 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.


intransitive verb
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

Nglish: Translation of react for Spanish Speakers

Britannica English: Translation of react for Arabic Speakers


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