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

Even when a seal is sedated though, the crew must remain alert as they are surrounded by fully awake, burly seals. Kasha Patel, Smithsonian, "How Data-Gathering Seals Help Scientists Measure the Melting Antarctic," 13 July 2018 The test operators, who are paid about $25 an hour, are trained to remain alert with their hands loosely on the wheel while the vehicles run preset routes. Greg Bensinger, WSJ, "Uber Cuts More Test Drivers in Its Robot Car Operation," 11 July 2018 The woman suffered multiple injuries and remained alert as rescuers got her to a hospital, according to park spokeswoman Dana Soehn, the Knoxville News Sentinel reported. Joe Marusak, charlotteobserver, "Woman was hiking at popular 80-foot mountain waterfall. Then she slipped.," 11 June 2018 Despite the name, Tesla (tsla, +1.49%) considers Autopilot to be a form of adaptive cruise control, in which drivers are still required to remain alert and be prepared to take action at any time during driving. Jonathan Sperling, Fortune, "Tesla Denies Autopilot Is to Blame for Brussels Crash," 31 May 2018 Officials urged pedestrians to always use a crosswalk and remain alert while crossing streets and drivers to avoid distractions while behind the wheel. Robert Gundran, azcentral, "Pedestrian hit, killed in west Phoenix, driver may have been impaired, police say," 2 May 2018 The driver is expected to remain alert and ready to take over if something comes up that the vehicle cannot handle. Cleve R. Wootson Jr., chicagotribune.com, "Tesla asserts Autopilot 'unequivocally makes the world safer' - days after fiery, fatal crash," 2 Apr. 2018 The passenger said Baker appeared alert and was speaking with a flight attendant after the woman moved her seat. BostonGlobe.com, "Woman says A.J. Baker groped her on flight, police say; Baker says he was asleep," 26 June 2018 After Cabrera’s double from the third slot, Jim Riggleman, the Reds’ alert interim manager, pointed out the error. New York Times, "Mets Bat Out of Turn in First and Lose on a Home Run in the 10th," 9 May 2018

Recent Examples on the Web: Noun

The test, scheduled for 2:18 pm ET, is the first trial of a national presidential alert system that will let any president issue a warning about a crisis. Recode Staff, Recode, "Recode Daily: A NYT financial investigation punctures Trump’s ‘self-made’ image," 3 Oct. 2018 Authorities also use electronic warning systems, including an emergency alert system that is repeated by local news media and an automated calling system that can be targeted to phones within a geographic area. Marcio Jose Sanchez And Sudhin Thanawala, Fox News, "Northern California wildfire 9th most destructive in history," 31 July 2018 This month, some of Hyundai Motor ’s 2019 Santa Fe models are hitting dealerships with a new rear-occupant alert system. Ellen Byron, WSJ, "Check the Back Seat! Alerts Remind Drivers About Children," 28 July 2018 Davis was last seen downtown Saturday afternoon leaving her house near the 900 block of East 10th Avenue, according to a police alert. Zaz Hollander, Anchorage Daily News, "Anchorage police say student intern from North Carolina found safe," 11 July 2018 The three people were taken to a nearby hospital around 7 p.m. Wednesday, including a 1-year-old child who was rushed as a trauma alert, said Fort Lauderdale police spokeswoman Casey Liening. Tonya Alanez, Sun-Sentinel.com, "Driver flees after hitting 3 pedestrians and several cars at Fort Lauderdale beach," 11 July 2018 At some point, a weather alert interrupted the fight. Tod Leonard, sandiegouniontribune.com, "Hurricane gave junior golfer Allyn Stephens perspective in game, life," 9 July 2018 One child was taken to Arnold Palmer Hospital for Children as a trauma alert, Proudfit said. Michael Williams, OrlandoSentinel.com, "Children injured in west Orange fireworks accident, officials say," 6 July 2018 Tony has his own reasons for attending the powwow, ones that take the story in a direction that is as contemporary, tragic, and American as a breaking news alert. Joan Gaylord, The Christian Science Monitor, "'There There' weaves a powerful tale of contemporary urban Native Americans," 2 July 2018

Recent Examples on the Web: Verb

The sergeant reported to the captain, who alerted Col. Michael M. Phillips, WSJ, "The One Time American Troops Fought Russians Was at the End of World War I—and They Lost," 9 Nov. 2018 The bad: Only Amazon cloud subscribers can set motion zones and receive person alerts. Cnet.com, The Seattle Times, "Hey, Alexa, which gadgets work the best with you?," 7 Nov. 2018 The lab was not staffed Saturday night, so when a local alarm sounded on the tank at 5:06 p.m., alerting anyone within earshot that the temperature had risen to –156 degrees Celsius, no one heard it. Kayla Webley Adler, Marie Claire, "When Your Dreams of Motherhood Are Destroyed," 1 Oct. 2018 Both Volexity and RiskIQ jointly discovered the attack and alerted Newegg this week which removed the code on Tuesday. Gordon Mah Ung, PCWorld, "Newegg confirms credit card information was taken in a sophisticated attack," 20 Sep. 2018 IceCube’s alerts generate a lot of interest among astronomers, because the neutrino represents the third arrow in the quiver of the newborn field of multimessenger astronomy. Mark Bowen, Scientific American, "Neutrinos on Ice: Astronomers' Long Hunt for Source of Extragalactic "Ghost Particles" Pays Off," 12 July 2018 The 21-year-old didn’t manage to find regular first team football at the Catalan side in his first season, which has alerted some clubs to his possible availability. SI.com, "Unai Emery Reportedly Identifies Barcelona Star Ousmane Dembele as the Club's Top Target This Summer," 10 July 2018 After the boy’s death, Bronin revealed that the pool’s surveillance system, which should have alerted a police dispatcher to the trespassing swimmers, had been broken, and that city officials had known it was broken. Ruth Bruno, courant.com, "Hartford Mayor Announces Plan For Policies To Maintain Security Cameras After 16-Year-Old Boy Drowns In Keney Park Pool," 6 July 2018 It is currently being used to alert doctors and nurses more quickly to patients at risk of acute kidney injury, a potentially fatal condition often first detected by blood tests rather than by a patient’s feeling unwell. The Economist, "Hospitals are learning from industry how to cut medical errors," 28 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

12 Nov 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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