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

Officials said Friday that the volcano’s alert status hadn’t changed, but that underground lava appears to be rising to the surface. Ben Otto, WSJ, "Bali Airport Reopens After Volcanic Ash Clears," 29 June 2018 The news outlets reported that the boy is alert and improving as of Wednesday morning at Cook Children's Medical Center in Abilene. Stephen English, star-telegram, "A Texas boy was playing with his toys. He was bitten by a rattlesnake hiding in them," 27 June 2018 Ridgely Middle School in Lutherville went on a short alert status Monday afternoon as police responded to a fight in the neighborhood, police said. Libby Solomon, baltimoresun.com, "Ridgely Middle on alert status Monday afternoon," 11 June 2018 The National Disaster Mitigation Agency said Friday the volcano's alert status, raised last month from the lowest level, is unchanged and a 3 kilometer no-go zone around the crater remains in force. Fox News, "Indonesia's Merapi volcano ejects towering column of ash," 1 June 2018 Three elementary schools were kept on alert status for hours, with students and teachers told to stay in their school buildings as police continued a search for the suspects. CBS News, "Intense hunt for suspects after Baltimore cop killed on duty," 22 May 2018 Three elementary schools were kept on alert status for hours, with students and teachers told to stay in their school buildings as police continued a search for the suspects. David Mcfadden And Sarah Rankin, USA TODAY, "Manhunt for suspects in female Baltimore police officer’s death," 22 May 2018 Three elementary schools were kept on alert status for hours, with students and teachers told to stay in their school buildings as police continued a search for the suspects. NBC News, "Manhunt for suspects in Baltimore area after officer killed," 22 May 2018 Tesla is extremely clear that Autopilot requires the driver to be alert and have hands on the wheel. Kirsten Korosec, Fortune, "Tesla Blames Driver in Latest Fatal Model X Crash," 11 Apr. 2018

Recent Examples on the Web: Noun

That data is used to send out bad-air alerts (the green, orange, and red warning days) and for regulatory purposes. Jason Plautz, WIRED, "Cheap, Portable Sensors Are Democratizing Air-Quality Data," 11 July 2018 Residents can pay taxes, sign up for important town alerts and read quarterly department updates on the town webletter. Courant Community, "Community News For The Enfield Edition," 10 July 2018 In the thriftiest mode, touchscreen, Bluetooth, vibration alerts, and optical heart rate are all shut off; the screen is dimmed to 10 percent and set to go dark after 10 seconds; and GPS is set to update every 120 seconds. Ariella Gintzler, Outside Online, "Testing the Suunto 9 Sports Watch," 6 July 2018 But the sophomore woke up the next day alert and responsive. Mark Wright, star-telegram, "Arlington Lamar used tragic moment as inspiration to keep 7-on-7 streak alive," 23 June 2018 Chief government spokesman Yoshihide Suga said the police were on alert for any attempts at retaliation for the executions. Alastair Gale, WSJ, "Japan Executes Leader of Doomsday Cult," 6 July 2018 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

Recent Examples on the Web: Verb

John Baccala, an Animal Control spokesman, told Fox 4 that the Snapchat video was dated May 22, and the Center High School principal alerted authorities May 24. Fox News, "Video of cat being kicked like football prompts search for kicker, camera operator," 20 June 2018 The law would require auto makers to install systems in all new cars alerting drivers to check the back seat once the car is turned off. Ellen Byron, WSJ, "Long Efforts to Stop Hot-Car Deaths," 2 May 2018 These allow for remote monitoring of individuals and their personal health data, providing reminders for when medications need to be taken and alerting medical authorities in case of a health emergency. Per Kristian Hong, STAT, "The 1 percent will continue to get healthier. The 99 percent should, too," 24 Apr. 2018 The device, usually worn on the ankle, can detect alcohol consumption through the skin, alerting authorities if the user has broken his or her probation by drinking. Emily Matchar, Smithsonian, "This Implantable Chip Could Monitor Alcohol Intake," 17 Apr. 2018 His mother alerted the authorities and delivered the money as instructed. Aaron Gell, Longreads, "Did Brian Easley Have to Die?," 9 Apr. 2018 Staff on that flight noticed something was wrong mid-flight and alerted the pilot. USA TODAY, "Passenger dies on United Airlines flight from Houston," 27 June 2018 Prosser said that while investigating, Powder Springs police alerted all metro Atlanta law enforcement agencies of the threats Bolieiro had made to kill the next cop who talked to him. Ben Brasch, ajc, "Cops: Cobb man arrested for threatening to kill police on Facebook," 11 June 2018 In one robbery, a barking dog alerted a sleeping couple to intruders,and the wife's 911 call forced the suspects to flee, Wang said. City News Service, sandiegouniontribune.com, "Two convicted of all charges in`Open Door Bandit' series," 4 June 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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Dictionary Entries near alert

Aleppo stone

alerce

alerion

alert

-ales

alesan

Alessandria

Statistics for alert

Last Updated

15 Oct 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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