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verb [intransitive/transitive] American English pronunciation: warn /wɔrn/ 
Word Forms
present tense
present participlewarning
past tensewarned
past participlewarned

Related dictionary definitions

  1. 1
    to make someone conscious of a possible problem or danger so that they will not be hurt
    warn someone to do something:

    Police are warning all women in the area to take extra care when going out alone.

    warn against:

    Recent studies warn against drinking too much caffeine.

    warn someone about something:

    Travel agents are not warning tourists about the dangers of crime in ski resorts.

    warn of:

    Scientists warned of the threat to beaches and rivers from pollution.

    warn that:

    The report warns that consumers could end up paying higher prices.

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