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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

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

  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


Medical Dictionary

react

play
intransitive 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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