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.

Definitions of prevent
  1. verb
    keep from happening or arising; make impossible
    synonyms: forbid, foreclose, forestall, preclude, preempt
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    make unnecessary, save
    make unnecessary an expenditure or effort
    avert, avoid, debar, deflect, fend off, forefend, forfend, head off, obviate, stave off, ward off
    prevent the occurrence of; prevent from happening
    block, blockade, embarrass, hinder, obstruct, stymie, stymy
    hinder or prevent the progress or accomplishment of
    baffle, bilk, confound, cross, foil, frustrate, queer, scotch, scuttle, spoil, thwart
    hinder or prevent (the efforts, plans, or desires) of
    block, halt, kibosh, stop
    stop from happening or developing
    obstruct or hinder any discussion
    disappoint, let down
    fail to meet the hopes or expectations of
    prevent commerce
    obstruct deliberately by delaying
    block or impede (a player from the opposing team) in ice hockey
    prevent from reaching a verdict, of a jury
    slow down or impede by creating an obstruction
    destroy or break
    hamper the progress of; impede
    destroy or cause to fail
    stop a judicial process
  2. verb
    stop (someone or something) from doing something or being in a certain state
    “We must prevent the cancer from spreading”
    synonyms: keep
    hold and prevent from leaving
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    allow, let, permit
    make it possible through a specific action or lack of action for something to happen
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    be on the defensive; act against an attack
    exclude, keep out, shut, shut out
    prevent from entering; shut out
    keep from departing
    keep away
    prevent from coming close
    keep the opposing (baseball) team from winning
    hinder, impede
    be a hindrance or obstacle to
    rain out, wash out
    prevent or interrupt due to rain
    take action to prevent someone else from acting
    curse, excommunicate, unchurch
    exclude from a church or a religious community
    defend with a bulwark
    protect, secure
    shield from danger, injury, destruction, or damage
    ward off
    avert, turn away, or repel
    arrest, check, contain, hold back, stop, turn back
    hold back, as of a danger or an enemy; check the expansion or influence of
    block, close up, impede, jam, obstruct, obturate, occlude
    block passage through
    lock out
    prevent employees from working during a strike
    limit, block, or decrease the action or function of
    come between so as to be hindrance or obstacle
    set back
    slow down the progress of; hinder
    hamper the action or progress of
    check the growth or development of
    ostracise, ostracize
    avoid speaking to or dealing with
Word Family

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