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react

play
verb re·act \rē-ˈakt\

Simple 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

Source: Merriam-Webster's Learner's Dictionary

Full Definition of react

  1. intransitive verb
  2. 1 :  to exert a reciprocal or counteracting force or influence —often used with on or upon

  3. 2 :  to change in response to a stimulus

  4. 3 :  to act in opposition to a force or influence —usually used with against

  5. 4 :  to move or tend in a reverse direction

  6. 5 :  to undergo chemical reaction

  7. transitive verb
  8. :  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.



Origin of react

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


First Known Use: 1644



REACT Defined for Kids

react

play
verb re·act \rē-ˈakt\

Definition of react for Students

reactedreacting

  1. 1 :  to act or behave in response to something <Firefighters reacted quickly to the situation.>

  2. 2 :  to oppose a force or influence Hint: In this sense, react is usually used with against. <Workers reacted against unfair treatment.>

  3. 3 :  to go through a chemical reaction <Acids react with bases to form salt.>




Medical Dictionary

react

play
verb re·act \rē-ˈakt\

Medical Definition of react

  1. 1:  to respond to a stimulus

  2. 2:  to undergo chemical reaction

  3. transitive verb

  4. :  to cause to react





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