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verb pre·vent \pri-ˈvent\

Simple Definition of prevent

  • : to stop (something) from happening or existing

  • : to make (someone or something) not do something : to stop (someone or something) from doing something

Source: Merriam-Webster's Learner's Dictionary

Full Definition of prevent

  1. transitive verb
  2. 1 archaic a :  to be in readiness for (as an occasion) b :  to meet or satisfy in advance c :  to act ahead of d :  to go or arrive before

  3. 2 :  to deprive of power or hope of acting or succeeding

  4. 3 :  to keep from happening or existing <steps to prevent war>

  5. 4 :  to hold or keep back :  hinder, stop —often used with from

  6. intransitive verb
  7. :  to interpose an obstacle

preventability play \-ˌven-tə-ˈbi-lə-tē\ noun
preventable also preventible play \-ˈven-tə-bəl\ adjective
preventer noun

Examples of prevent in a sentence

  1. Seatbelts in cars often prevent serious injuries.

  2. Can exercise and a healthy diet prevent heart disease?

  3. The accident could have been prevented.

  4. He grabbed my arm to prevent me from falling.

  5. Bad weather prevented us from leaving.

  6. How are you going to prevent him from finding out about the party?

Origin of prevent

Middle English, to anticipate, from Latin praeventus, past participle of praevenire to come before, anticipate, forestall, from prae- + venire to come — more at come

First Known Use: 15th century

Synonym Discussion of prevent

prevent, anticipate, forestall mean to deal with beforehand. prevent implies taking advance measures against something possible or probable <measures taken to prevent leaks>. anticipate may imply merely getting ahead of another by being a precursor or forerunner or it may imply checking another's intention by acting first <anticipated the question by making a statement>. forestall implies a getting ahead so as to stop or interrupt something in its course <hoped to forestall the sale>.

PREVENT Defined for Kids


verb pre·vent \pri-ˈvent\

Definition of prevent for Students


  1. 1 :  to keep from happening <Helmets help to prevent injuries.>

  2. 2 :  to hold or keep back <Bad weather prevented us from leaving.>

preventable \pri-ˈven-tə-bəl\ adjective

Seen and Heard

What made you want to look up prevent? Please tell us where you read or heard it (including the quote, if possible).


a timid, meek, or unassertive person

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