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

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

But several states have already established housing designated as LGBT-friendly, where there are social events, activities, and discussions geared to the interests of gay and lesbian residents and the staff is trained to be alert to their concerns. Robert Weisman, BostonGlobe.com, "Gay boomers look ahead to an old age colored by uncertainty and the help of friends," 9 June 2018 The state Department of Transportation advises drivers to be alert for potential pavement problems and traffic slowdowns. Sarah Hauer, Milwaukee Journal Sentinel, "It was record-breaking hot out today — so hot that pavement is buckling," 27 May 2018 Both the state’s SunPass operators and the expressway authority’s E-PASS managers are warning drivers to monitor their accounts and to be alert to automatic charges to their credit cards on file. Kevin Spear, OrlandoSentinel.com, "SunPass recovering from customer-service debacle, posting toll charges made weeks ago," 10 July 2018 Furthermore, the company didn’t want to alert authorities, perhaps fearful that the press would find out, and the company’s valuation would be affected. Nick Bilton, The Hive, "“Threats,” “Ultimatums,” and “Espionage”: Inside Silicon Valley’s Spy Wars," 13 Apr. 2018 But even earth-dwellers experience their fair share of problems with sleep—about 1 in 5 Americans struggle with getting to bed at night or staying alert during the day. Lara Sorokanich, Popular Mechanics, "The Most Useful Podcast Ever: 3 Tips for Sleeping Better Than an Astronaut," 21 Sep. 2015 But forecasters also cautioned that people should be alert for possible heavy rain that could cause flooding or mudslides. Washington Post, "Beryl dissipates after Dominica, easing threat to others," 9 July 2018 The injuries were not life-threatening and the two people were alert when they were transported to the hospital, said Andrew Ethridge, a spokesman for Volusia County Beach Safety Ocean Rescue. Annie Martin, OrlandoSentinel.com, "2 adults hit by car in New Smyrna Beach," 5 July 2018 Signs have been posted on Miami's campus warning people to be alert for falling limbs. Fox News, "University trying to save its iconic ash trees from borers," 1 July 2018

Recent Examples on the Web: Noun

An automatic alert went out less than a minute later. Daniel Clery, Science | AAAS, "Ghostly particle caught in polar ice ushers in new way to look at the universe," 12 July 2018 The arrest of Russell Hamlen, 29, came shortly after police Tuesday morning had issued a public alert seeking tips about his location. Alex Demarban, Anchorage Daily News, "Anchorage police catch suspect who they say fled after ramming SUV through garage wall," 3 July 2018 Students wound up alerting the Metropolitan Police Department, the story said, and on April 3, a crime alert was issued. Valerie Strauss, Washington Post, "Howard University issues new warning of flasher in chemistry building," 22 June 2018 Then, on Friday, the State Department issued a health alert for any American visitors to China—though don't go canceling your trip just yet. Laura Dannen Redman, Condé Nast Traveler, "U.S. State Department Issues Health Alert for China—What It Actually Means," 11 June 2018 On Friday, the US State Department issued a fresh health alert for workers there. Beth Mole, Ars Technica, "US pulls two more from Cuba amid puzzling health cases now affecting China," 11 June 2018 Related If suspicious changes are seen, GLAD alerts are sent to local communities or authorities on the ground. Katarina Zimmer /, NBC News, "These tiny 'guardians' are helping protect the world's forests," 11 May 2018 Those vents prompted Hawaii County to issue a cellphone alert ordering stragglers in Lanipuna Gardens to leave immediately. CBS News, "NASA satellite photos show lava-oozing volcano fissures on Hawaii's Big Island," 9 May 2018 The alert is issued when cases involving missing persons that do not meet Amber Alert criteria. Detroit Free Press Staff, Detroit Free Press, "Missing Michigan girl, 12, found safe in Florida," 8 May 2018

Recent Examples on the Web: Verb

Officers sent to 22 Dexter St., near the Wethersfield line, shortly before 11:30 p.m. after the ShotSpotter gunshot detection system alerted them to one round being fired in the area found a man who had been shot on the left thigh, police said. Christine Dempsey, courant.com, "Hartford PD: Two Shootings In Same Neighborhood In Three Hours," 27 June 2018 The mother, who'd been alerted by text, intervened and the man eventually fled the scene. Cincinnati.com, "Reading police: Man followed teen with intention of having sexual intercourse," 12 June 2018 Soyuncu is considered by many as one of Europe's most promising centre backs, featuring 26 times in the Bundesliga last season, with his performances alerting the likes of the Gunners, Liverpool and Atletico Madrid. SI.com, "Freiburg Star's Agent Confirms Arsenal Have Held 'Concrete Talks' Over Defender," 9 June 2018 The ceremony likely surprised hikers, who passed signs alerting to animals, water stops, climbing conditions and more. Alison Steinbach, azcentral, "Connecticut couple hikes into Grand Canyon to say 'I do'," 6 June 2018 San Diego County Sheriff's Department deputies responded to a burglary in the 14000 block of Palisades Drive Monday afternoon and were alerted by a neighbor that a man was seen running away from the residence, said sheriff's Lt. City News Service, Pomerado News, "Poway residents help deputies capture burglary suspect," 30 May 2018 Hawaii County officials were knocking on doors on several streets in the Leilani Estates subdivision alerting residents to flee fast-moving lava from the Kilauea volcano. CBS News, "Hawaii officials go door to door to get holdouts to flee fast lava," 29 May 2018 Later in the clip, the officer opens the door to another room and alerts its residents that an gunman is in the hotel. NBC News, "First police video of Las Vegas concert massacre released," 2 May 2018 Last week Principal Bob McBride sent a message via the Indian Prairie District 204 notification system alerting Neuqua Valley families that a Neuqua student who made online gun violence threats had been arrested and charged by Naperville police. Suzanne Baker, Naperville Sun, "STEPS parents miffed they weren't included in Neuqua Valley alert about gun threat arrest," 30 Apr. 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

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

Noun

see alert entry 1

Verb

see alert entry 1

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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

17 Sep 2018

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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Comments on alert

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