alert

adjective
\ ə-ˈlərt How to pronounce alert (audio) \

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

Synonyms: Noun

Synonyms: Verb

Antonyms: Adjective

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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 Severson said the alert system isn't perfect, but is useful nonetheless. Bruce Vielmetti, Milwaukee Journal Sentinel, "Suspect in custody for Waukesha County Courthouse bomb threat, sheriff's department says," 6 Jan. 2020 The Alaska Department of Transportation launched Friday the 511 road condition alert system designed to be more user- and mobile-friendly, the Anchorage Daily News reported. USA TODAY, "Puppy wins lotto, alligators, mountain lions, Dunkin Donuts wedding: News from around our 50 states," 30 Dec. 2019 The Alaska Department of Transportation on Friday rolled out a new 511 road condition alert system that brings together crowdsourced data and navigation to give drivers the most up-to-date information possible. Tess Williams, Anchorage Daily News, "Get real-time road and traffic conditions with the new Alaska 511 system," 27 Dec. 2019 High on the wall hangs a clock above a row of seven stars, part of an old-fashioned alert system designed to get representatives to the floor in time to vote. Tom Sietsema, Washington Post, "Now you can eat at the Capitol just like a U.S. representative: Badly," 4 Dec. 2019 Maryland’s alert system is hard for even medical professionals to understand. John Diedrich, jsonline.com, "Some busy hospitals say they must turn away ambulances. Here's how one state banned the practice," 22 Nov. 2019 So far, Hyundai and sibling brand Kia are the only ones rolling out a more advanced detection and alert system. NBC News, "Italy just introduced a law it hopes will reduce hot car deaths. Why hasn't the U.S.?," 8 Nov. 2019 Hanford police said that the baby was not believed to have been in danger, a key requirement for the California Highway Patrol alert system. Colleen Shalby, Los Angeles Times, "Baby found several hours after being taken by possible father, police say," 15 Oct. 2019 The freezer has been replaced, the sensor monitoring and alert system has been upgraded, power sources have been double checked, maintenance has been increased, and engineering staff are being trained on the new system, the hospital said. San Diego Union-Tribune, "Stem cells lost in freezer failure at Children’s Hospital LA," 27 Sep. 2019 Recent Examples on the Web: Noun The rush on supplies was sparked by the Ministry of Health’s decision to increase its Disease Outbreak Response System Condition (Dorscon) rating to Orange—the second highest level of public health alert. Eamon Barrett, Fortune, "Singapore urges calm—but its tourism industry is being pummeled by the coronavirus outbreak," 11 Feb. 2020 The county now allows property owners to sign up for a fraud alert that sends notifications if someone tries to grab their land. Robert Wilonsky, Dallas News, "A ‘reverend’ forged deed on $4M foreclosed Dallas mansion, court records say. The bank wants it back.," 7 Feb. 2020 The cancellations followed a U.S. State Department travel alert, warning Americans not to travel to China because of the serious health risk. Randy Diamond, ExpressNews.com, "Coronavirus strands Chinese professor and family in San Antonio," 7 Feb. 2020 Police issued a silver alert that night and an amber alert for Vanessa two days later. Monica Haider, CNN, "Connecticut man charged with killing his girlfriend, baby still missing," 7 Feb. 2020 Day 10 30 60 90 120 The day W.H.O. issued a global alertregarding the outbreak. National Geographic, "How coronavirus compares to flu, Ebola, and other major outbreaks," 7 Feb. 2020 Multiple incidents of catalytic converters being stolen off vehicles have been reported to the Dearborn Police Department, according to a Nixle alert sent Monday. Darcie Moran, Detroit Free Press, "Thieves target Honda Civics in Dearborn, police say," 4 Feb. 2020 As of Thursday, the CDC listed a travel alert of Level 3, avoid all nonessential travel to China. Julie Washington, cleveland, "Coronavirus at a glance: Staying healthy, international travel, resources," 30 Jan. 2020 Evers called on the Department of Agriculture, Trade and Consumer Protection to: Issue a consumer alert about the hazards of youth vaping. Mary Spicuzza, Milwaukee Journal Sentinel, "Gov. Tony Evers unveils sweeping plan aimed at combating youth vaping," 19 Jan. 2020 Recent Examples on the Web: Verb Authorities in Chicago are praising a jogger who spotted a man in the freezing waters of Lake Michigan over the weekend and alerted police. Fox News, "Chicago police officers pull man from Lake Michigan on 'coldest day of the year'," 18 Feb. 2020 Noah then went to get his uncle next door, who helped alert the other sleeping family members in the burning house. Caitlin O'kane, CBS News, "5-year-old boy pulls sister and dog out of window during a house fire, saving their lives," 14 Feb. 2020 His father, Karel Kral, was the United Nations reporter for the Czechoslovak news agency CTK, and in that capacity helped alert the world to the threat of a Soviet invasion of his country, which came about two years later. Jim Farber, BostonGlobe.com, "Ivan Kral, rocker with Patti Smith and others, is dead at 71," 6 Feb. 2020 The victims reported the abuse to the diocese, which alerted Dallas police. David Tarrant, Dallas News, "Lawsuit says Dallas diocese did not protect young girl from priest’s abuse," 1 Feb. 2020 The hospital subsequently found traces of morphine in the urine of the babies and alerted police. NBC News, "German nurse suspected of drugging 5 babies with morphine," 30 Jan. 2020 The monitors also will alert police and warn engineers. Terry Spencer, chicagotribune.com, "New higher-speed Florida train has the highest death rate in the nation. Most of the deaths have been suicides.," 2 Dec. 2019 The student alerted police, who used surveillance video and ID scanner footage from a bar that Mucaj and Karal were at that night to track them down. David Owens, courant.com, "UConn student arrested for shouting racial slur has case continued," 30 Oct. 2019 Marley alerted on a duffel bag full of cash in the backseat of the vehicle. Mike Cruz, azcentral, "$800,000 in cash in duffel bag found by Glendale police K-9 during traffic stop," 1 Feb. 2020

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

borrowed from French alerte, going back to Middle French a l'herte "on guard, on the watch," borrowed from Italian all'erta, originally in the collocation stare all'erta "to be on the watch," literally, "to be on the height" (with erta "height, hill, steep ascent," noun derivative from feminine of erto, past participle of ergere "to raise, elevate," going back to Vulgar Latin *ērgere, by syncope from Latin ērigere) — more at erect entry 1

Note: The earliest citation for the word in the Oxford English Dictionary suggests direct borrowing from Italian, or at least recognition of an Italian source: "In this place the Prince [of Orange] finding his rutters [cavalry soldiers] alert, (as the Italians say) with aduise of his valiant brother, hee sent his Trumpets to D. d' Alua…." (Sir Roger Williams, The Actions of the Lowe Countries, London, 1618, p. 27).

Noun

noun derivative of alert entry 1 (or borrowed from French alerte, derivative of alerte, adjective)

Verb

verbal derivative of alert entry 1 or alert entry 2

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Time Traveler for alert

Time Traveler

The first known use of alert was in 1618

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Statistics for alert

Last Updated

19 Feb 2020

Cite this Entry

“Alert.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/alert. Accessed 27 Feb. 2020.

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More Definitions for alert

alert

adjective
How to pronounce alert (audio)

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 How to pronounce alert (audio) \

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.

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

Thesaurus: All synonyms and antonyms for alert

Rhyming Dictionary: Words that rhyme with alert

Spanish Central: Translation of alert

Nglish: Translation of alert for Spanish Speakers

Britannica English: Translation of alert for Arabic Speakers

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