react

play
verb re·act \ rē-ˈakt \

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

Examples of react in a Sentence

  1. When I told her what happened, she reacted with anger.

  2. I didn't expect him to react that way.

  3. The firefighters reacted quickly when they heard the alarm.

  4. He reacted badly to the drug.

Recent Examples of react from the Web

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.

Origin and Etymology of react

New Latin reactus, past participle of reagere, from Latin re- + agere to act — more at agent

react Synonyms

Synonyms
reply, respond
Related Words
answer, return; retaliate; construe, interpret, read, take, understand; contend (with), cope (with), grapple (with), handle, manage, negotiate
Near Antonyms
act, behave; affect, cause, draw, effect


REACT Defined for English Language Learners

react

play
verb

Definition of react for English Language Learners

  • : 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 Defined for Kids

react

play
verb re·act \ rē-ˈakt \

Definition of react for Students

reacted; reacting
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.

Medical Dictionary

react

play
intransitive verb 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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