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1

alert

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adjective \ə-ˈlərt\

Simple Definition of alert

  • : able to think clearly and to notice things

Source: Merriam-Webster's Learner's Dictionary

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

alertly

adverb

alertness

noun

Examples of alert in a sentence

  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 and Etymology 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>.

2

alert

noun

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)

Source: Merriam-Webster's Learner's Dictionary

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 in a sentence

  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.



1803

First Known Use of alert

1803


3

alert

verb

Simple Definition of alert

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

  • : to make (someone) aware of something

Source: Merriam-Webster's Learner's Dictionary

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 in a sentence

  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



ALERT Defined for Kids

1

alert

play
adjective \ə-ˈlərt\

Definition of alert for Students

  1. 1 :  watchful and ready especially to meet danger <But he was alert at night, too, on the road, always listening intently … — Lois Lowry, The Giver>

  2. 2 :  quick to understand and act <An alert reader noticed the error in grammar.>

alertly

adverb <The prairie dog sat alertly beside the opening of its burrow.>

alertness

noun



2

alert

play
noun

Definition of alert for Students

  1. 1 :  an alarm or signal of danger <The police issued an alert.>

  2. 2 :  the period during which an alert is in effect <We stayed indoors during the alert.>

on the alert

  1. :  watchful against danger <… the remark had set us all on the alert, straining ears and eyes … — Robert Louis Stevenson, Treasure Island>




3

alert

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verb

Definition of alert for Students

alerted

alerting

  1. :  to make aware of a need to get ready or take action :  warn <The siren alerted us that a tornado was approaching.>





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