prevented; preventing; prevents
Synonyms of prevent

transitive verb

1
: to keep from happening or existing
steps to prevent war
2
: to hold or keep back : hinder, stop
—often used with from
3
: to deprive of power or hope of acting or succeeding
4
archaic
a
: to be in readiness for (something, such as an occasion)
b
: to meet or satisfy in advance
c
: to act ahead of
d
: to go or arrive before

intransitive verb

: to interpose an obstacle
preventable adjective
preventer noun
Choose the Right Synonym for 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

Examples of prevent in a Sentence

Seatbelts in cars often prevent serious injuries. Can exercise and a healthy diet prevent heart disease? The accident could have been prevented. He grabbed my arm to prevent me from falling. Bad weather prevented us from leaving. How are you going to prevent him from finding out about the party?
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
One of the sources had said last week that reported TPLF restrictions on mobile communications may be part of a tactic to neutralize government forces' advantage in using battlefield drones, by preventing them from accessing the mobile network. — Arkansas Online, 26 Sep. 2026 There is carp fencing between the river and the canal in the Lemont area, which may or may not prevent carp from getting into the canal in flood stage. — Chicago Tribune, 26 Sep. 2026 Some studies suggest fasting may also help prevent cancer or boost the effectiveness of chemotherapy, though much of that research is still preliminary. — Hanna Wickes, Charlotte Observer, 25 Sep. 2026 The challenge is that the cost of prevention is visible today, while the value of preventing a mistake is invisible unless something goes wrong. — George Achilleos, Forbes.com, 25 Sep. 2026 See All Example Sentences for prevent

Word History

Etymology

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, in the meaning defined at sense 4c

Time Traveler
The first known use of prevent was in the 15th century

Cite this Entry

“Prevent.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/prevent. Accessed 28 Sep. 2026.

Kids Definition

1
: to keep from happening
prevent accidents
2
: to hold or keep back : hinder, stop
bad weather prevented us from leaving
preventable adjective
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