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Synonyms

alert

American  
[uh-lurt] / əˈlɜrt /

adjective

  1. fully aware and attentive; wide-awake; keen.

    She had an alert mind.

    Synonyms:
    observant, wary, awake
    Antonyms:
    unaware
  2. swift; agile; nimble.

    Synonyms:
    spirited, sprightly, active, quick, lively, brisk

noun

  1. an attitude of vigilance, readiness, or caution, as before an expected attack.

  2. a warning or alarm of an impending military attack, a storm, etc..

    We'd just boarded the bus when the alert sounded.

  3. the period during which such a warning or alarm is in effect.

verb (used with object)

  1. to warn (troops, ships, etc.) to prepare for action.

  2. to warn of an impending raid, attack, storm, etc..

    The radio alerted coastal residents to prepare for the hurricane.

  3. to advise or warn; cause to be on guard.

    to alert gardeners to the dangers of some pesticides.

idioms

  1. on the alert, on guard against danger; in readiness; vigilant.

    The state police are on the alert for an escaped convict believed to be in the area.

alert British  
/ əˈlɜːt /

adjective

  1. vigilantly attentive

    alert to the problems

  2. brisk, nimble, or lively

"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

noun

  1. an alarm or warning, esp a siren warning of an air raid

  2. the period during which such a warning remains in effect

    1. on guard against danger, attack, etc

    2. watchful; ready

      on the alert for any errors

"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

verb

  1. to warn or signal (troops, police, etc) to prepare for action

  2. to warn of danger, an attack, etc

"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
alert More Idioms  

Usage

What does alert mean? An alert is a warning or alarm, especially an alarm about dangerous weather or a military attack, as in The National Weather Service has alerts for tornadoes, hurricanes, Nor’easters, and other severe weather occurrences.Alert is also an attitude of readiness or caution, as in Tina was on alert for news of her son’s acceptance into college.Alert describes being fully attentive or wide awake, as in Sabine needs to be awake for several hours before she is alert and ready to work. You can be alert to the people and objects surrounding you. When you are alert, you’re ready to act or react instead of being surprised. But you can also be alert to concepts, ideas, and trends, ready to react to a change in others’ thoughts or to a change in the market.To alert means to advise or to warn, as with an alert. For example, your teacher might alert you that your big project is due soon, while a police department might alert the public about a dangerous person on the streets.Example: Alert the security team of the incident and then head home.

Related Words

Alert, vigilant, watchful imply a wide-awake attitude, as of someone keenly aware of their surroundings. Alert describes a ready and prompt attentiveness together with a quick intelligence: The tourist was alert and eager to see the sights. Vigilant suggests some immediate necessity for keen, active observation, and for continuing alertness: Knowing the danger, the scout was unceasingly vigilant. Watchful suggests carefulness and preparedness: A stakeout requires watchful waiting.

Other Word Forms

  • alertly adverb
  • alertness noun
  • hyperalert adjective
  • unalerted adjective

Etymology

Origin of alert

First recorded in 1590–1600; 1940–45 alert for def. 4; from Italian all'erta, equivalent to all ( a ) “to, on the” + erta “lookout, watchtower,” originally feminine of erto, past participle of ergere from Latin ērigere to erect

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.

Police said they were alerted to the incident at the farm on Chelford Road by the fire and rescue service.

From BBC

As a result, newer, more subtle technologies for monitoring—in-home radar instead of cameras, wearables that provide other benefits and only trigger alerts when there’s a real emergency—are gaining in popularity.

From The Wall Street Journal

OpenAI said it did not alert authorities to the account because its usage did not meet its threshold of a credible or imminent plan for serious physical harm to others.

From BBC

Pham said he belongs to a regional dealer network in which members alert one another when burglaries happen nearby, sharing suspect descriptions and stolen inventory lists.

From Los Angeles Times

Online platforms have long debated how to balance questions of privacy for their users with public safety in their decisions to alert certain users to law enforcement.

From The Wall Street Journal