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Synonyms

prevent

American  
[pri-vent] / prɪˈvɛnt /

verb (used with object)

  • prevents,
    present (3rd person singular)
  • prevented,
    past participle,  past
  • preventing
    present participle
  1. to keep from occurring; avert; hinder.

    He intervened to prevent bloodshed.

    Synonyms:
    thwart, obviate, preclude, forestall, obstruct
    Antonyms:
    assist, help
  2. to hinder or stop from doing something.

    There is nothing to prevent us from going.

  3. Archaic. to act ahead of; forestall.

  4. Archaic. to precede.

  5. Archaic. to anticipate.


verb (used without object)

  • prevents,
    present (3rd person singular)
  • prevented,
    past participle,  past
  • preventing
    present participle
  1. to interpose a hindrance.

    He will come if nothing prevents.

prevent British  
/ prɪˈvɛnt /

verb

  1. (tr) to keep from happening, esp by taking precautionary action

  2. to keep (someone from doing something); hinder; impede

  3. (intr) to interpose or act as a hindrance

  4. archaic (tr) to anticipate or precede

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Synonym Usage

Prevent, hamper, hinder, impede refer to different degrees of stoppage of action or progress. To prevent is to stop something effectually by forestalling action and rendering it impossible: to prevent the sending of a message. To hamper is to clog or entangle or put an embarrassing restraint upon: to hamper preparations for a trip. To hinder is to keep back by delaying or stopping progress or action: to hinder the progress of an expedition. To impede is to make difficult the movement or progress of anything by interfering with its proper functioning: to impede a discussion by demanding repeated explanations.

Other Word Forms

Derived Forms

Inflected Forms

Participles

Conjugated Forms

Present

Past

Future


Etymology

Origin of prevent

First recorded in 1375–1425; late Middle English, from Latin praeventus “anticipated,” past participle of praevenīre “to anticipate,” equivalent to prae- pre- ( def. ) + venīre “to come”


Explanation

The verb prevent means "to keep something from happening," like when you use a complicated password to prevent hackers from accessing your account. Prevent comes from the Latin word praeventus, meaning "to act in anticipation of," like when you shovel the icy, snow-covered sidewalk to prevent people from falling. Prevent can also mean "to make impossible," like when a school locks the doors during a dance to prevent kids from leaving without their parents knowing.

Keep Reading on Vocabulary.com

Vocabulary lists containing prevent

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

Outside Khartoum, most wheat supplies arrive in the form of aid, but fuel shortages and spiralling prices, along with road closures due to the fighting, prevent deliveries.

From Barron's ● Nov. 5, 2026

In his address, Egyptian Foreign Minister Badr Abdelatty said, “We have to push very hard in order to prevent the escalation.”

From Los Angeles Times ● Nov. 4, 2026

Even if the body continues producing HGF, chemical changes may prevent the protein from properly activating the stem cells needed for tissue repair.

From Science Daily ● Nov. 4, 2026

Ancient woodland campaigners fear a drive to build more houses could put some of England's oldest habitats under increasing pressure, despite government protections designed to prevent their loss.

From BBC ● Nov. 4, 2026

The important thing, with the big Paris summit coming up, was to prevent a crisis with the Soviet Union.

From "Fallout: Spies, Superbombs, and the Ultimate Cold War Showdown" by Steve Sheinkin

The script’s air of inevitability prevents it from mustering up much suspense.

From Los Angeles Times ● Nov. 4, 2026

Virginia and other states are trying to slow ‘super speeders’ with GPS technology that prevents their cars from blowing the speed limit.

From The Wall Street Journal ● Nov. 3, 2026

The mouse experiments demonstrated protection against tissue damage, but they did not establish that the strategy prevents colorectal cancer.

From Science Daily ● Oct. 31, 2026

The system prevents people who register with it from accessing gambling websites and apps licensed in Great Britain.

From BBC ● Oct. 31, 2026

The only thing that prevents me from going all the way down is the side of the mathlete trophy case hanging on the wall.

From "Popcorn" by Rob Harrell

The problem with this explanation is that it is doubtful that the government’s information prevented the statute-of-limitations period from expiring.

From Slate ● Nov. 3, 2026

Lowering amyloid beta in the bloodstream does not necessarily mean that amyloid plaques in the brain will decrease or that Alzheimer's disease can be prevented.

From Science Daily ● Nov. 3, 2026

Surely that prevented the striker from being able to play the ball?

From BBC ● Nov. 2, 2026

In the past, that secretive atmosphere has prevented information about other infectious outbreaks from becoming public, including an anthrax outbreak in 2016 in the Siberian province of Yamal that officials said killed two people.

From The Wall Street Journal ● Oct. 30, 2026

Major provisions of the Affordable Care Act had also gone into effect, with young people allowed to remain longer on their parents’ insurance policies and companies prevented from capping a patient’s lifetime coverage.

From "Becoming" by Michelle Obama

Caroline Choi, Edison’s executive vice president of public policy and corporate affairs, told The Times that the proposal would not change the utilities’ focus on preventing fires.

From Los Angeles Times ● Nov. 3, 2026

The loss lands largely on shareholders, who can’t withdraw their paid-in capital, preventing a run on the company’s coffers.

From The Wall Street Journal ● Nov. 2, 2026

Radev has also argued that a ceasefire and peace talks offer the best chance of preventing further attacks on commercial shipping in the Black Sea.

From Barron's ● Nov. 1, 2026

An experimental treatment aimed at preventing the return of the type of cancer Teddy has is no longer available in the UK, so his family raised £250,000 to access the vaccine trial in New York.

From BBC ● Oct. 31, 2026

Meggie was clutching the book tightly, as if that were the only way of preventing yet more misfortunes from creeping out of it.

From "Inkheart" by Cornelia Funke

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