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adjective \ə-ˈlərt\

Simple Definition of alert

  • : able to think clearly and to notice things

Full Definition of alert

  1. 1 a :  watchful and prompt to meet danger or emergency b :  quick to perceive and act

  2. 2 :  active, brisk

alert·ly adverb
alert·ness noun

Examples of alert

  1. An alert guard stopped the robbers.

  2. He was tired and had trouble staying alert while he was driving.

  3. She wasn't mentally alert enough to answer the questions.

  4. An alert watchdog guarded the door.

Origin of alert

Italian all'erta, on the watch, literally, on the height

First Known Use: 1618

Synonym Discussion of alert

watchful, vigilant, wide-awake, alert mean being on the lookout especially for danger or opportunity. watchful is the least explicit term <the watchful eye of the department supervisor>. vigilant suggests intense, unremitting, wary watchfulness <eternally vigilant in the safeguarding of democracy>. wide-awake applies to watchfulness for opportunities and developments more often than dangers <wide-awake companies latched onto the new technology>. alert stresses readiness or promptness in meeting danger or in seizing opportunity <alert traders anticipated the stock market's slide>.

intelligent, clever, alert, quick-witted mean mentally keen or quick. intelligent stresses success in coping with new situations and solving problems <an intelligent person could assemble it fast>. clever implies native ability or aptness and sometimes suggests a lack of more substantial qualities <clever with words>. alert stresses quickness in perceiving and understanding <alert to new technology>. quick-witted implies promptness in finding answers in debate or in devising expedients in moments of danger or challenge <no match for his quick-witted opponent>.




Simple Definition of alert

  • : something (such as a message or loud sound) that tells people there is some danger or problem : an alarm or signal of danger

  • : the state of being ready for something you have been warned about (such as an attack)

Full Definition of alert

  1. 1 :  a state of careful watching and readiness especially for danger or opportunity <on 24-hour alert>

  2. 2 a :  an alarm or other signal of danger b :  an urgent notice <an alert to parents … about new immunization requirements — Ann Schrader>

  3. 3 :  the period during which an alert is in effect

Examples of alert

  1. They sounded an alert when enemy planes were approaching the city.

  2. Medical officials have put out an alert to hospitals to look out for the virus.

  3. The government has issued a terrorism alert.


First Known Use of alert





Simple Definition of alert

  • : to give (someone) important information about a possible problem, danger, etc. : to warn (someone)

  • : to make (someone) aware of something

Full Definition of alert

  1. transitive verb
  2. 1 :  to call to a state of readiness :  warn

  3. 2 :  to make aware of <alerted the public to the dangers of pesticides>

Examples of alert

  1. Several neighbors alerted the authorities when they noticed strangers acting suspiciously.

  2. The governor alerted island residents that a hurricane was coming.

  3. The teacher alerted the students that tests would be given the next day.

Circa 1868

First Known Use of alert

circa 1868

Seen and Heard

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February 14, 2016

to hug and kiss another person

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