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warn

v.
US //ˈwɔɹn// UK //wˈɔːn// warn
  1. 1 to alert to danger (v.)
    B1 Intermediate

    to tell someone that something bad or dangerous might happen.

    to inform someone in advance of an impending danger, problem, or other unpleasant situation. Transitive, often taking a direct object followed by 'of' or 'about'.

    Example

    The radio announcer warned drivers about the thick fog on the motorway.

    Example

    Meteorologists warned the coastal residents of the approaching storm, urging them to evacuate before the surge reached the lower streets.

    Usage

    Commonly used in the patterns 'warn someone of something' or 'warn someone that...'.

    Pitfall
    He warned me to not go there.
    He warned me not to go there.

    When using 'warn' with an infinitive, the 'not' should come before 'to'.

  2. 2 to advise against an action (v.)
    B1 Intermediate

    to tell someone not to do something because it is a bad idea.

    to caution or admonish someone against a specific course of action or unacceptable behaviour.

    Example

    My doctor warned me not to eat too much salt.

    Example

    The legal advisor warned the board against signing the contract without a thorough review of the indemnity clauses.

    Usage

    Often followed by 'against' plus a gerund, or 'not to' plus an infinitive.

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  1. 3 to order away (v.)
    B2 Upper Intermediate

    to tell someone they must leave a place or stay away from it.

    to advise or formally order someone to depart or to remain at a distance. Often used with 'off'.

    Example

    The security guard warned the teenagers off the private property.

    Example

    The farmer used a loud whistle to warn the hikers off his fields during the lambing season.

    Usage

    Frequently appears as the phrasal verb 'warn off'.

Origin

From Middle English warnen, warnien (“to warn; admonish”), from Old English warnian (“to take heed; warn”), from Proto-Germanic warnōną (“to warn; take heed”), from Proto-Indo-European wer- (“to be aware; give heed”). Cognate with Dutch waarnen (obsolete), German Low German warnen, German warnen, Swedish varna, Icelandic varna.

Word family

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