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

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.
Recent Examples on the Web America’s heady pay gains could mean that the Fed has to react more aggressively to slow down the economy. New York Times, 25 Apr. 2022 The Ducks scored three goals in less than 10 minutes of the first period, with the typically steady young goaltender Karel Vejmelka seemingly a tick too slow to react to the shots. José M. Romero, The Arizona Republic, 1 Apr. 2022 For decades, antitrust bodies in Europe and the US have been perceived as ineffective and too slow to react. Javier Espinoza, Ars Technica, 21 Mar. 2022 The world has to react, Kushnir said, because children are dying and the millions of people who have fled Ukraine likely won’t have a home to return to. Alexandra Kukulka,, 17 Mar. 2022 By March 2020, the government had to react to a large wave of the disease, and the federal and local governments instituted a series of lockdowns. Vikram Mittal, Forbes, 17 Mar. 2022 New England had to react to everything the Bills were doing, and in the end, Buffalo rolled 33-21. Sal Maiorana, USA TODAY, 16 Jan. 2022 The movement was so strong that the conservative legal system had to react and at least one alleged serial rapist was arrested by the police . Somayeh Malekian, ABC News, 4 Jan. 2022 If the Fed’s policy were still to proactively address threats of faster inflation in the future, then observers could well argue that the Open Market Committee’s stance has been too loose and policy makers too slow to react to rising inflation. Dana M. Peterson, WSJ, 16 Dec. 2021 See More

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.

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

11 May 2022

Cite this Entry

“React.” Dictionary, Merriam-Webster, Accessed 17 May. 2022.

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More Definitions for react


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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