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REFERENCE

alert

adj. · v. · n.
US //əˈɫɝt// UK //ɐlˈɜːt// alert
  1. 1 watchful (adj.)
    B1 Intermediate

    watching and listening carefully so that you notice things quickly.

    fully aware and attentive; wide awake and ready to act or respond.

    Example

    The security guard stayed alert throughout the night to keep the building safe.

    Example

    Despite the long hours of the flight, the pilot remained alert and responded immediately to the slight change in engine vibration.

  2. 2 to warn (v.)
    B2 Upper Intermediate

    to tell someone about a danger or a problem so they can be ready.

    to notify someone of a potential danger, problem, or important event.

    Example

    A neighbor called to alert us that our garage door was still open.

    Example

    The intelligence agency acted quickly to alert the local authorities about the credible threat to the public event.

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  1. 3 a warning (n.)
    B1 Intermediate

    a message or signal that warns people of danger.

    a signal, such as a siren or digital notification, that warns of an immediate danger or important condition.

    Example

    The phone sent out a loud alert to warn everyone about the coming storm.

    Example

    The system triggered an automatic alert when the server temperature exceeded the safe operating limit.

  2. 4 readiness (n.)
    B2 Upper Intermediate Military

    a state of being ready for a sudden attack or danger.

    a condition of heightened watchfulness or preparation for action, especially in a military or emergency context.

    Example

    The army was on high alert after the peace talks failed.

    Example

    The coastal defenses were placed on full alert following reports of unidentified vessels entering territorial waters.

Etymology 1

From French alerte (“alert”), from the phrase à l'erte (“on the watch”), from Italian all'erta (“to the height”), from erta (“lookout, tower”).

Etymology 2

Formed within English by conversion, from alert (adjective). Compare French alerter.

Word family

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