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 Following the incident, which took place in late October, the Florida Wildlife Federation urged locals to stay alert in order to avoid potential clashes in the future. Washington Post, "Video shows man wrestling puppy from alligator’s jaws without dropping his cigar," 23 Nov. 2020 Campbell said the district’s plan is still to return to full remote learning if Cuyahoga County goes to Level 4 (purple) -- the highest alert level on the Ohio Public Health Advisory System. cleveland, "Orange Schools’ return to in-person learning going well, despite one active student case of COVID-19," 9 Nov. 2020 Pro Trailer Backup Assist takes over many of the reversing tasks, leaving the driver to stay alert, follow directions and turn a knob. Jeff Yip, Houston Chronicle, "Ford next-generation 2021 F-150s just around the corner," 16 Oct. 2020 However, the National Weather Service said there's a lot of uncertainty in the track and residents from northern Mexico to Florida should stay alert. Carlie Wells, NOLA.com, "Hurricane expected to form in Gulf of Mexico this weekend: See latest track," 18 Sep. 2020 Residents of foothill communities east of Los Angeles were being told to stay alert because of a fire in the Angeles National Forest. John Bacon, USA TODAY, "15 firefighters injured in California as wind-driven wildfires roar across West," 10 Sep. 2020 Redfield also said that as many as 60 million Americans could have contracted the virus, adding that while cases should start dropping around parts of the country by next week, many in middle America need to stay alert. Tara John, CNN, "What you need to know about coronavirus on Friday, August 21," 21 Aug. 2020 Authorities said residents could return home Thursday but encouraged them to stay alert in case weather or fire conditions change. oregonlive, "Oregon wildfires burn throughout state, from Columbia River Gorge to California border," 20 Aug. 2020 Stay alert and be prepared to take shelter if threatening weather approaches. Tynin Fries, The Denver Post, "Denver weather: Afternoon thunderstorms could bring hail, 70 mph winds to Eastern Plains," 19 July 2020 Recent Examples on the Web: Noun River and flash flooding may soon follow along with dangerous storm surge that is likely to bring water levels up by as much as 10 to 15 feet, the National Hurricane Center said in a 1 a.m. alert. Madeline Holcombe, CNN, "Hurricane Iota brings catastrophic winds and likely life-threatening flooding just miles from where Eta made landfall," 17 Nov. 2020 All of Honduras was on high alert, with compulsory evacuations that began before the weekend. The Associated Press, NOLA.com, "Hurricane Iota, a Category 5 storm, heads for same area battered by Hurricane Eta," 16 Nov. 2020 In Honduras, compulsory evacuations began before the weekend and by Sunday evening 63,500 people were reported to be in 379 shelters just in the northern region, while the whole country was on high alert. Fox News, "Hurricane Iota becomes Category 4 storm, new threat to Central America," 16 Nov. 2020 The blood bank needs convalescent plasma to treat people with severe COVID-19 infections, the Anchorage Office of Emergency Management said in an alert Friday morning. Anchorage Daily News, "Blood Bank of Alaska issues urgent appeal for people who had COVID-19 to donate plasma," 13 Nov. 2020 The city has been on high alert since Sunday, when a worker at a cold-storage facility tested positive. WSJ, "Coronavirus Live Updates: U.S. Cases Top 100,000 for Ninth Day Running," 12 Nov. 2020 The order was lifted Friday night in consultation with law enforcement agencies investigating the threats, the university said in a campus alert. NBC News, "Threats over Black Lives Matter mural prompt lockdown at campus in North Carolina," 10 Oct. 2020 In an alert published on Tuesday, the Department of Homeland Security’s Cybersecurity and Infrastructure Agency and the Multi-State Information Sharing & Analysis Center said LokiBot activity has scaled up dramatically in the past two months. Dan Goodin, Ars Technica, "“LokiBot,” the malware that steals your most sensitive data, is on the rise," 22 Sep. 2020 The boy was declared dead at the scene by emergency responders, the sheriff’s office said in a news alert around 5:40 p.m. oregonlive, "14-year-old boy killed at Hagg Lake after boating accident, officials say," 29 Aug. 2020 Recent Examples on the Web: Verb These tools could form the basis of an early warning system to alert authorities to online narratives that pose a threat in the real world. Timothy R. Tangherlini, The Conversation, "An AI tool can distinguish between a conspiracy theory and a true conspiracy – it comes down to how easily the story falls apart," 13 Nov. 2020 New plans also include mobile device tracking that would alert people when they have been exposed to the virus, the Star Tribune reports. From Usa Today Network And Wire Reports, USA TODAY, "Football fan penalty, first pitch, charcoal treatment: News from around our 50 states," 10 Nov. 2020 In the future, that information could be relayed to MnDOT's traffic management center, which in turn could alert the State Patrol. Tim Harlow, Star Tribune, "MnDOT testing system on downtown Minneapolis freeway ramp to prevent wrong-way drivers," 28 Oct. 2020 Time your movements with the squirrel’s and be aware of twigs or other obstacles on the ground that could alert the animals to your presence. Johnny Carrol Sain, Outdoor Life, "The Ultimate Guide to Hunting Squirrels," 6 Oct. 2020 Microsoft is testing a new feature for Windows 10 that will alert you if your SSD drive is failing. Mark Hachman, PCWorld, "Is your SSD failing? Microsoft is testing a Windows 10 feature that will tell you," 1 Oct. 2020 Columnist Leila Atassi pushes for schools to alert parents of positive test results in the classroom (without identifying the child) as soon as the school hears of it. Cliff Pinckard, cleveland, "Documents show FirstEnergy pressures state lawmakers to get what it wants: The Wake Up for Friday, Aug. 28, 2020," 28 Aug. 2020 That’s in addition to the typical heart rate sensor, which will automatically alert you if your beat is unusually fast or slow when compared to your activity level. Stan Horaczek, Popular Science, "The new Fitbit knows when you’re stressed—and how to help you chill," 25 Aug. 2020 What is lacking is a coherent federal strategy to alert Americans to the consequences of inaction. David Oshinsky, Scientific American, "How We Can Avoid a 'Twindemic' of COVID and Flu," 4 Nov. 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

1 Dec 2020

Cite this Entry

“Alert.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/alert. Accessed 1 Dec. 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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