alert

1 of 3

adjective

1
a
: 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
alertly adverb
alertness noun

alert

2 of 3

noun

1
: a state of careful watching and readiness especially for danger or opportunity
on 24-hour alert
2
a
: 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

alert

3 of 3

verb

alerted; alerting; alerts

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
Phrases
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
Choose the Right Synonym for alert

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. See More
Recent Examples on the Web
Adjective
None of them challenge that convention, yet Wilson is alert to the ambivalence in their stoicism. Judith Thurman, The New Yorker, 11 Sep. 2023 The company says their alert system– from AI detection to the dispatch of law enforcement – takes less than 30 seconds. Lauren Lantry, ABC News, 7 Sep. 2023 Expect delay and be alert for debris from other vehicles on the highway at higher speeds. Christina Maxouris, CNN, 5 Sep. 2023 Nuun Sport + Caffeine Nuun Sport + Caffeine is the perfect electrolyte powder for runners who are looking to boost their energy levels and stay alert during workouts. Amber Smith, Discover Magazine, 29 Aug. 2023 And therein may lie perhaps the biggest difference between Hilary and the other two tropical storms that most recently hit Southern California: the National Weather Service had recently bolstered its operations and alert systems for this exact situation. Grace Toohey, Los Angeles Times, 28 Aug. 2023 In the wake of a flash flood, be alert to any information about water contamination, as things like sewage and chemical waste can be present in floodwaters and affect drinking water systems. Sarah Raza, BostonGlobe.com, 12 Sep. 2023 The victims were alert and breathing when they were taken to a hospital. David Aaro, ajc, 10 Sep. 2023 Texas residents may be asked to conserve again during the eclipse, and the novelty of the event could help overcome grid alert fatigue amid a summer of near-record heat for the state. Bloomberg Wire, Dallas News, 8 Sep. 2023
Noun
Be the first to know about the biggest and best luxury home sales and listings by signing up for our Mansion Deals email alert. Katherine Clarke, WSJ, 22 Sep. 2023 The neighboring states of Tamil Nadu and Karnataka have been on high alert, and no new cases have been reported there, though these states have less vigilant health surveillance systems compared to Kerala. Efficient, Lucky—or Both? WIRED, 22 Sep. 2023 My colleagues over at Fortune Crypto have been following this whole debacle rather closely (so much so that one of our crypto reporters, Ben Weiss, even built a Slack bot that automatically spits out alerts every time a new document is filed in Bankman-Fried’s criminal case file). Jessica Mathews, Fortune, 21 Sep. 2023 Give your iPhone inbound ringtone, notifications and alert sounds a makeover immediately. Kurt Knutsson, Fox News, 20 Sep. 2023 Commands are accompanied with visual feedback from the Dynamic Island bar — home to alerts and notifications at the top of the screen. Samantha Murphy Kelly, CNN, 19 Sep. 2023 Officials then received alerts that Sanchez and Rice’s ankle monitors had been tampered with. City News Service, San Diego Union-Tribune, 17 Sep. 2023 The alert would not be the first in California to address a specific group. Karen Garcia, Los Angeles Times, 16 Sep. 2023 Should your driver need you, the device has buttons to send a manual alert to communicate in an emergency or send a primitive text. Cheryl Fenton, Parents, 14 Sep. 2023
Verb
Manson must also alert police to any concerts planned for New Hampshire for the next two years and complete his community service by Sunday, February 4, 2024. Jazz Monroe, Pitchfork, 19 Sep. 2023 Strong antivirus software actively running on your devices will alert you of any malware in your system, warn you against clicking on any malicious links in phishing emails, and ultimately protect you from being hacked. Kurt Knutsson, Fox News, 19 Sep. 2023 Activists at times alerted conservative media outlets to their leads, generating headlines about new investigations. Sharon Lafraniere, New York Times, 18 Sep. 2023 Narcotics investigators arrested Jorge Alas-Avila, 31, on Southwest Broadway and Jefferson Street after a drug-sniffing dog alerted a plainclothes officer to the presence of fentanyl in his Mercedes, according to court records. oregonlive, 15 Sep. 2023 Five-year-old A.J. Freund’s life could have been saved if child welfare workers had alerted other specialists about his case, two former county prosecutors and a doctor testified Thursday. Robert McCoppin, Chicago Tribune, 14 Sep. 2023 Officers outside the pub were not aware of the fights inside, the department said in a statement, and no one on the scene requested medical assistance for any injuries or alerted the police. Nathan Solis, Los Angeles Times, 14 Sep. 2023 Then, late Monday, a motorist alerted police to a man matching Mr. Cavalcante’s description crouching in the darkness along a line of trees near a road in northern Chester County. Maryclaire Dale, Marc Levy, and Michael Rubinkam, The Christian Science Monitor, 13 Sep. 2023 The cut also alerted scientists to the fact that the eruption had disrupted the seafloor, which isn’t easy to spot. Rahul Rao, Popular Science, 7 Sep. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'alert.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

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

First Known Use

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

Time Traveler
The first known use of alert was in 1618

Dictionary Entries Near alert

Cite this Entry

“Alert.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/alert. Accessed 25 Sep. 2023.

Kids Definition

alert

1 of 3 adjective
1
a
: being watchful and ready to meet danger
b
: quick to understand and act
2
alertly adverb
alertness noun

alert

2 of 3 noun
1
: a signal of danger
2
: the period during which an alert is in effect

alert

3 of 3 verb
: to call to a state of readiness : warn

More from Merriam-Webster on alert

Last Updated: - Updated example sentences
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