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.
Recent Examples on the Web
Adjective
The country remained neutral in both World Wars but when Russian troops began marching toward Kyiv in February 2022, Sweden – and its Nordic neighbor Finland – became alert to the threat Moscow could pose to nearby countries outside the alliance. Christian Edwards, CNN, 7 Mar. 2024 Prebble is alert to the evolution of narrative in the digital age, and likes to think about how writers and directors might adapt to new technologies. Rebecca Mead, The New Yorker, 4 Mar. 2024 Additionally, using basic project management tools like calendars with alert notifications and making lists can help track the progress of your goals more effectively. Britney Porter, Forbes, 29 Feb. 2024 Rather, as burrowing species who establish their single-spider homes underground, tarantulas sling webs to act as molting mats or as alert systems signaling whenever someone – an unwitting prey or a prospective mate – approaches their doorsteps. Katie Liu, Discover Magazine, 29 Feb. 2024 In recent years, the U.S. foreign policy establishment has become more alert to matters of race. Naima Green-Riley, Foreign Affairs, 23 Feb. 2024 Heavy rain was expected all night, while another low-pressure system on Monday’s forecast raised concerns among weather officials, who advised residents to stay alert. Grace Hase, The Mercury News, 18 Feb. 2024 Be alert for skimming devices in tourist areas, which are popular targets. Dalia Faheid, Fort Worth Star-Telegram, 30 Jan. 2024 With water temperatures climbing to unprecedented heights, NOAA earlier this month added three new levels to its alert system to account for increasingly severe coral bleaching and higher mortality rates. Helen Regan, CNN, 28 Feb. 2024
Noun
But Sunday's incident also comes at a time when the media and the public are on high alert over artificial intelligence and its ability to create realistic images—and, increasingly, voices and video—from simple prompts. Brian Barrett, WIRED, 11 Mar. 2024 The warning is below a red flag alert, a higher level of fire warning issued by the agency, said Andrew Quigley, a local NWS meteorologist. David Clarey, Journal Sentinel, 11 Mar. 2024 For Mayor Lorin Palmer, the first alert about changes underway in the town of Herriman, Utah, came from a school principal. Sarah Matusek, The Christian Science Monitor, 7 Mar. 2024 An active shooter alert went out to all school parents, Keast said, noting James Crumbley went home to check for the gun. Gina Kaufman, Detroit Free Press, 7 Mar. 2024 The alert includes a way for users to find their representative and call their office. Mia Sato, The Verge, 7 Mar. 2024 The State Department issued a travel alert to U.S. citizens over the weekend urging them to leave Haiti immediately. Jacqueline Charles, Miami Herald, 6 Mar. 2024 On the same screen, Kayak offers travelers the ability to set a price alert to get notified when airfares change for this particular flight. Stella Shon, Travel + Leisure, 6 Mar. 2024 The alert is for Erath, Hood and Somervell counties. Star-Telegram Bot, Fort Worth Star-Telegram, 6 Mar. 2024
Verb
In this scenario, the IIHS says the vehicles should automatically begin an emergency slowdown and alert local emergency services. Popular Science, 13 Mar. 2024 Beech Grove police officers were first alerted to the situation on Jan. 14, 2023, by a neighbor who reported the boy had a handgun and was pointing it at people, according to the probable cause affidavit for Osborne’s arrest. Jake Allen, The Indianapolis Star, 12 Mar. 2024 Alas, Liu’s spider-sense didn’t alert him to the insidious plot that was about to unfold. Wesley Stenzel, EW.com, 12 Mar. 2024 President Roosevelt’s purpose was to wake up the Congress and alert the American people that this was no ordinary moment. USA TODAY, 8 Mar. 2024 Storm alerts from the National Weather Service Fort Worth office in the past two days have warned of up to quarter-sized hail and damaging winds for the area. Tiffani Jackson, Fort Worth Star-Telegram, 8 Mar. 2024 Alaska State Troopers were alerted by Race Marshal Warren Palfrey that the moose’s body remained on the trail. Charna Flam, Peoplemag, 6 Mar. 2024 Ahead of the opening, officials went to local restaurants, including Mama’s Pizza Kitchen and Busyboys and Poets, to alert them to an influx of lunchtime customers, and representatives from the D.C. police briefed workers on what to expect. Jenna Portnoy, Washington Post, 1 Mar. 2024 The girl’s mother soon alerted the other parents and arrived at Meyden’s house to pick up her daughter. Sean Neumann, Peoplemag, 1 Mar. 2024

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 19 Mar. 2024.

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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