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 South Africa has also excelled at clear communication, including strategic use of an alert-level system that empowers people to understand their risk and helps the government make transparent and balanced decisions about closures. Tom Frieden, WSJ, "Which Countries Have Responded Best to Covid-19?," 1 Jan. 2021 At the red, or second-most serious alert level, Gurka will decide whether to remain in the all-remote model or return some grades to in-person learning or a combination of remote and in-person education. Bob Sandrick, cleveland, "North Royalton teachers to receive 2.5-percent raises under one-year contract extension," 28 Dec. 2020 The Kilauea Volcano observatory raised the alert level to warning, an advisory said. Madeline Holcombe, CNN, "Hawaii residents told to stay home as Kilauea volcano erupts," 21 Dec. 2020 The alert level is judged by factors like new cases per capita, a sustained increase in new cases and intensive care unit bed capacity in the region. Jackie Borchardt, The Enquirer, "Coronavirus in Ohio: Will Hamilton, Clermont and Warren counties go 'purple'?," 3 Dec. 2020 Nottinghamshire was the latest area to enter the highest tier on Friday, while West Yorkshire will move to the same alert level from Monday. Alex Morales, Bloomberg.com, "Covid Spreading Faster Than U.K. Scientists’ Worst-Case Scenario," 30 Oct. 2020 The state health department considers the Mat-Su region to be at a high alert level because of widespread community transmission. Tess Williams, Anchorage Daily News, "Mat-Su schools postpone indoor sport competitions until end of October," 19 Oct. 2020 Quebec Premier Francois Legault said the two biggest cities in the Canadian province are returning to the highest COVID-19 alert level. Rob Gillies, Star Tribune, "Quebec, Ontario in second COVID-19 wave; restrictions return," 28 Sep. 2020 Schools, team sports and heart damage Earlier this month, Dallas County moved our alert level to orange from red for the first time. Anna Kuchment, Dallas News, "Medical experts discuss COVID-19 trials and when a vaccine might be available in North Texas.," 21 Sep. 2020 Recent Examples on the Web: Noun In mid-December, authorities escalated Mexico City’s alert system to the highest level — red — which requires an immediate shutdown of all but essential businesses. New York Times, "Fleeing Lockdown, Americans Are Flocking to Mexico City," 2 Jan. 2021 In mid-December, authorities escalated Mexico City’s alert system to the highest level — red — which requires an immediate shutdown of all but essential businesses. Oscar Lopez, BostonGlobe.com, "Fleeing lockdown, Americans are flocking to Mexico City," 2 Jan. 2021 The state’s affidavit justifying the warrant, however, notes that state employees shared the same username and password for the emergency alert system. al, "Rebekah Jones: Florida COVID dashboard whistleblower’s home raided," 13 Dec. 2020 The search was part of a criminal investigation into unauthorized messages sent last month to a group of health department employees using an internal emergency alert system. Patricia Mazzei New York Times, Star Tribune, "Florida virus-numbers saga reads like a crime novel," 12 Dec. 2020 Jones has denied sending the message, though court records show that the alert system can be accessed via a username and password that many department employees share. CBS News, "Bodycam footage shows Florida agents' raid on fired COVD scientist's home," 11 Dec. 2020 The state’s affidavit justifying the warrant, however, notes that state employees shared the same username and password for the emergency alert system. Skyler Swisher, sun-sentinel.com, "Cybersecurity lax for ‘very sensitive’ emergency alert system at the center of the Rebekah Jones raid," 11 Dec. 2020 The alert system was launched at the beginning of July. Rich Exner, cleveland, "Cuyahoga remains on red alert for coronavirus; Lake and Lorain improve from purple to red," 10 Dec. 2020 The warrant stemmed from an investigation into an alleged hack of the Department of Health’s messaging alert system used for emergencies. Fox News, "Florida cops raid home of scientist who said she was fired for not doctoring COVID-19 data," 8 Dec. 2020 Recent Examples on the Web: Verb Dauber hopes that an AI that routinely scrutinizes images for hints of new craters, and can alert scientists to them within days or weeks of their formation, will teach us more about Martian history. Daniel Oberhaus, Wired, "NASA Is Training an AI to Detect Fresh Craters on Mars," 19 Jan. 2021 Be vigilant: If exposed in a parking lot or on the street, be aware of your surroundings, alert for potential threats. Granville Lawrence, Star Tribune, "We the people must take back the streets of our city," 1 Dec. 2020 According to police, Lopez-Herrera had activated the rapid flashing beacons which alert oncoming traffic to pedestrians before entering the crosswalk. oregonlive, "Man dies 10 days after hit-and-run in Southeast Portland," 29 Nov. 2020 Their role is to exchange intelligence, de-conflict reports, and quickly alert law enforcement officials who make interdictions on the high seas. Abraham Mahshie, Washington Examiner, "Trump's counternarcotics strategy nets 216 metric tons of cocaine and 74K pounds of marijuana worth $5.7B," 24 Nov. 2020 The Detroit Police Department plans to present a proposal to the City Council on Monday that would allow sound sensors that alert police of gunshots to be placed in the city. Omar Abdel-baqui, Detroit Free Press, "DPD to start using gunshot detection technology ShotSpotter if City Council approves," 19 Nov. 2020 Ask a fellow passenger to put their mask on or alert a flight attendant if someone is being lax. Dawn Gilbertson, USA TODAY, "Low risk or dicey? Two new reports paint different pictures of COVID-19 danger while flying," 27 Oct. 2020 This registration process, mandated by federal law, is crucial so that in the event of a safety recall, the tire manufactures can alert affected drivers, according to the suit. Bethany Rodgers, The Salt Lake Tribune, "Utah solicitor general apologizes, agrees to pay $3,750 for erroneous court filing," 28 Sep. 2020 In August, according to Anderson, UNT contacted some partners to alert them of significant funding issues, and to tell them to stop sending samples for DNA analysis. Michael Schulson/undark, Popular Science, "Our best missing persons database could disappear in a few months," 28 Dec. 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

12 Jan 2021

Cite this Entry

“Alert.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/alert. Accessed 26 Jan. 2021.

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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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Comments on alert

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