alert

adjective
\ ə-ˈlərt \

Definition of alert

 (Entry 1 of 3)

1a : watchful and prompt to meet danger or emergency an alert guard trying to stay alert to possible problems
b : quick to perceive and act mentally alert
2 : active, brisk elicited an alert response

alert

noun

Definition of alert (Entry 2 of 3)

1 : a state of careful watching and readiness especially for danger or opportunity on 24-hour alert
2a : an alarm or other signal of danger traffic alerts They sounded the alert.
b : an urgent notice … an alert to parents … about new immunization requirements.— Ann Schrader
3 : the period during which an alert is in effect
on the alert
: looking for or expecting something (such as danger or an opportunity) Drivers need to be on the alert for icy condition. always on the alert for a good bargain

alert

verb
alerted; alerting; alerts

Definition of alert (Entry 3 of 3)

transitive verb

1 : to call (someone) to a state of readiness : warn alerted the school board of a possible teachers' strike alert the authorities
2 : to make (someone) aware of something alerted the public to the dangers of pesticides

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Other Words from alert

Adjective

alertly adverb
alertness noun

Synonyms & Antonyms for alert

Synonyms: Adjective

Argus-eyed, attentive, awake, observant, open-eyed, tenty (also tentie) [Scottish], vigilant, watchful, wide-awake

Synonyms: Noun

admonishment, admonition, alarm (also alarum), caution, forewarning, heads-up, notice, warning

Synonyms: Verb

advise, caution, forewarn, wake, warn

Antonyms: Adjective

asleep

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Choose the Right Synonym for alert

Adjective

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

Examples of alert in a Sentence

Adjective

An alert guard stopped the robbers. He was tired and had trouble staying alert while he was driving. She wasn't mentally alert enough to answer the questions. An alert watchdog guarded the door.

Noun

They sounded an alert when enemy planes were approaching the city. Medical officials have put out an alert to hospitals to look out for the virus. The government has issued a terrorism alert.

Verb

Several neighbors alerted the authorities when they noticed strangers acting suspiciously. The governor alerted island residents that a hurricane was coming. The teacher alerted the students that tests would be given the next day.
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Recent Examples on the Web: Adjective

Far from being lost in meditation, the figure’s expression is alert and its gaze direct, its eyes perhaps once inlaid with rock crystal or gemstones. Lee Lawrence, WSJ, "‘The Jeweled Isle: Art From Sri Lanka’ Review: Reclaiming a Country’s Creative History," 1 Jan. 2019 It should never be allowed to be activated if the driver is not alert and responsive. Jonathan M. Gitlin, Ars Technica, "Elon Musk promises big new Tesla Autopilot upgrade, but is it legal?," 10 Dec. 2018 Police said the victim was alert and able to speak. Jessica Anderson, baltimoresun.com, "Man found shot, lying in the street in North Baltimore," 4 Apr. 2018 Even the best intentions won't keep you from tossing and turning with excitement, though, which is why the 2019 Nissan Altima comes with features designed to help fatigued drivers stay alert. Brigitt Earley, Woman's Day, "6 Ways to Stay Safe on Your Next Family Road Trip," 29 Nov. 2018 Last year, Crate & Barrel started their Black Friday sales earlier than usual, so stay alert. Jolie Peters, House Beautiful, "The Best Places To Score A Sofa On Black Friday," 14 Oct. 2018 Stay alert and look for road crews, turning cars, or other hazards though. Caroline Picard, Good Housekeeping, "QUIZ: Could You Still Pass a Basic Driver’s Ed Test?," 30 July 2018 Stay alert to weather changes that may impact hiking or other activities. David Swanson, latimes.com, "National parks where you can find solitude in summer," 1 July 2018 Good team defender who rebounds, communicates, and stays alert. Sean Meagher, OregonLive.com, "NBA draft rumors: Chandler Hutchison secures 1st-round draft promise," 17 May 2018

Recent Examples on the Web: Noun

These antioxidant-like compounds may help counteract chronic inflammation, a physiological state where your body's cells stay on high alert due to a lingering or past threat. Caroline Picard, Good Housekeeping, "The 5 Best Health Benefits of Ginger Water," 11 Jan. 2019 But researchers are on alert now in an effort to help pregnant women across the globe stay ahead of the curve. Macaela Mackenzie, Glamour, "Rift Valley Fever Could Be the Next Global Health Crisis For Pregnant Women," 10 Jan. 2019 Greece's civil protection services went on alert Thursday as the country braced for the threat of a cyclone, forest fires prompted evacuations on an island and an earthquake rattled the south of the country. Elena Becatoros And Derek Gatopoulos, Fox News, "Cyclone warning as gale-force winds batter Greece," 27 Sep. 2018 But nothing was normal about this day, from the temperatures in the high 80s to a soccer-crazed country on high World Cup alert. Karen Crouse, New York Times, "Wimbledon Has a New Doubles Event: Tennis and the World Cup," 7 July 2018 Liverpool are on high alert after the chances of Paulo Dybala leaving Juventus increased as the Serie A giants continue their stunning pursuit of Cristiano Ronaldo, according to reports in Italy. SI.com, "Italian Report Provides Positive Update on Possible Liverpool Move for Juventus Star," 7 July 2018 Most days, zoo officials are on high alert to ensure zoo animals don't get loose. Christina Lords, idahostatesman, "Wild bear breaks into S. Idaho zoo, climbs tree to wait out Fish and Game officials," 3 July 2018 Your Dog Asks For Help This new snoring fix has CPAP makers on high alert. Reader Submitted, Cincinnati.com, "Anniversaries: Glenn Richardson & Gertrude Richardson," 1 July 2018 Newsrooms across the country were on high alert after the rampage, putting more security in place around news organizations. Editors, USA TODAY, "Capital Gazette shooting, ESPN Body Issue, Toys R Us: 5 things to know Friday," 29 June 2018

Recent Examples on the Web: Verb

The Ohio liberal-arts college sent an email blast last Tuesday alerting high-school seniors that the deadline had been extended to Feb. 1. Melissa Korn, WSJ, "Oberlin, University of Chicago and Other Elite Colleges Extend Application Deadlines," 29 Jan. 2019 When the Guardian alerted Facebook to this, the social media company switched off the function within hours. Casey Newton, The Verge, "How Kevin Hart tweeted himself out of a job hosting the Oscars," 8 Dec. 2018 Matthew Crane, 28, was found dead in Mill Creek, two miles from the Mohegan Sun Pocono casino in Plains Township, Pa. Crane had worked at the gambling center as a table dealer before alerting authorities in 2015 about a major scam taking place. Bradford Betz, Fox News, "Key witness in casino fraud case found dead in creek," 13 Sep. 2018 Drivers will be alerted to weeknight and weekend lane closures as the work is scheduled, GDOT said. David Ibata, ajc, "New lane opens on Ga. 400 in Forsyth," 13 July 2018 Officers were dispatched at 10:34 p.m. to the 4700 block of Magoun Avenue after police were alerted of shots fired by ShotSpotter, Detective Sgt. Becky Jacobs, Post-Tribune, "Man fatally shot in East Chicago alley, police say," 11 July 2018 Police were alerted to people breaking into the dealership, in the 5300 block of Airline near Tidwell, around 2:30 a.m., said Lt. Samantha Ketterer, Houston Chronicle, "Police nab four suspects in burglary at north Houston car dealership," 11 July 2018 Sign up for the resort’s email list to be alerted to the periodic 48-hour sales where rooms are discounted between 30 and 40 percent. New York Times, "Looking for a Weekend Escape? Here Are 5 Family-Friendly Options," 6 July 2018 Use the links to the left in a feed reader application to be alerted about articles. Hartford Courant, courant.com, "RSS FEEDS," 5 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'alert.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of alert

Adjective

1618, in the meaning defined at sense 1a

Noun

1801, in the meaning defined at sense 1

Verb

circa 1868, in the meaning defined at sense 1

History and Etymology for alert

Adjective, Noun, and Verb

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

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Learn More about alert

Dictionary Entries near alert

Aleppo stone

alerce

alerion

alert

-ales

alesan

Alessandria

Statistics for alert

Last Updated

22 Jan 2019

Look-up Popularity

Time Traveler for alert

The first known use of alert was in 1618

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More Definitions for alert

alert

adjective

English Language Learners Definition of alert

 (Entry 1 of 3)

: able to think clearly and to notice things

alert

noun

English Language Learners Definition of alert (Entry 2 of 3)

: 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)

alert

verb

English Language Learners Definition of alert (Entry 3 of 3)

: to give (someone) important information about a possible problem, danger, etc. : to warn (someone)
: to make (someone) aware of something

alert

adjective
\ ə-ˈlərt \

Kids Definition of alert

 (Entry 1 of 3)

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

Other Words from alert

alertly adverb The prairie dog sat alertly beside the opening of its burrow.
alertness noun

alert

noun

Kids Definition of alert (Entry 2 of 3)

1 : an alarm or signal of danger The police issued an alert.
2 : the period during which an alert is in effect We stayed indoors during the alert.
on the alert
: watchful against danger … the remark had set us all on the alert, straining ears and eyes …— Robert Louis Stevenson, Treasure Island

alert

verb
alerted; alerting

Kids Definition of alert (Entry 3 of 3)

: 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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More from Merriam-Webster on alert

Rhyming Dictionary: Words that rhyme with alert

Thesaurus: All synonyms and antonyms for alert

Spanish Central: Translation of alert

Nglish: Translation of alert for Spanish Speakers

Britannica English: Translation of alert for Arabic Speakers

Comments on alert

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