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

Synonyms & Antonyms for alert

Synonyms: Adjective

Argus-eyed, attentive, awake, observant, open-eyed, tenty (also tentie) [Scottish], vigilant, watchful, wide-awake

Synonyms: Noun

admonishment, admonition, alarm (also alarum), caution, forewarning, heads-up, notice, warning

Synonyms: Verb

advise, caution, forewarn, wake, warn

Antonyms: Adjective

asleep

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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

Even the best intentions won't keep you from tossing and turning with excitement, though, which is why the 2019 Nissan Altima comes with features designed to help fatigued drivers stay alert. Brigitt Earley, Woman's Day, "6 Ways to Stay Safe on Your Next Family Road Trip," 29 Nov. 2018 Last year, Crate & Barrel started their Black Friday sales earlier than usual, so stay alert. Jolie Peters, House Beautiful, "The Best Places To Score A Sofa On Black Friday," 14 Oct. 2018 Stay alert and look for road crews, turning cars, or other hazards though. Caroline Picard, Good Housekeeping, "QUIZ: Could You Still Pass a Basic Driver’s Ed Test?," 30 July 2018 Stay alert to weather changes that may impact hiking or other activities. David Swanson, latimes.com, "National parks where you can find solitude in summer," 1 July 2018 Good team defender who rebounds, communicates, and stays alert. Sean Meagher, OregonLive.com, "NBA draft rumors: Chandler Hutchison secures 1st-round draft promise," 17 May 2018 Stay alert to avoid unpleasant surprises in a Chicago spring. Beth Botts, chicagotribune.com, "'Don’t be in a rush to plant everything': Chicago's volatile spring tricky for gardeners," 9 May 2018 For the best chance to see wildlife, venture out early or late in the day, don’t talk, don’t look at your phone, and instead stay alert for distant movement and be ready to home in with binoculars. Tom Stienstra, San Francisco Chronicle, "Sunday drive to Marin County’s Limantour Beach," 25 Mar. 2018 Those who have not yet been vaccinated are urged to get a flu shot, and parents are encouraged to get their children vaccinated and stay alert for early warning signs. Jamie Ducharme, Time, "Healthy 12-Year-Old Florida Boy Dies Suddenly From the Flu, Family Says," 25 Jan. 2018

Recent Examples on the Web: Noun

The feature, called Always Together, is an automatic alert that will go off if the jacket moves too far away from your phone. Dani Deahl, The Verge, "Google and Levi’s smart jacket can now warn you if you’re about to leave your phone behind," 9 Dec. 2018 On the bright side: Every model in our test features a dishwasher-safe basket and audible alerts when cooking is complete. Betty Gold, Good Housekeeping, "The 5 Best Air Fryers for Making Crispy Comfort Foods So Much Healthier," 20 Nov. 2018 Follow Us Comment in Backfires to share your opinion, and follow us on Facebook, YouTube, and Twitter to stay on top of all things C/D. Subscribe Subscribe to the magazine, download apps, and sign up for our e-mail newsletter and text alerts. Car and Driver, "Oops! It seems you've reached a dead end.," 18 Nov. 2018 Officers found the Minnesota native alert and conscious, but highly intoxicated with a strong smell of alcohol in her breath, police said. Katherine Lam, Fox News, "'One of the worst DUI offenders in the US' arrested with liquor bottle in passenger seat: cops," 2 Oct. 2018 According to a pre-storm analysis from the National Low-Income Housing Coalition, nearly 280,000 very low-income renter households reside in counties where hurricane, storm surge, or tropical storm alerts have been issued due to Florence. Patrick Sisson, Curbed, "Flood insurance is broken," 20 Sep. 2018 FEMA’s app provides real-time alerts about the weather and locates emergency shelters in your area. Megan Friedman, Country Living, "How to Protect Your Pet During Hurricane Florence," 11 Sep. 2018 John Scardino, 58, a high school teacher from the United States who has lived in Britian for 18 years and will be at Friday’s protests in London, is dubious that the embassy alert would have any effect on crowd size. Karla Adam, Washington Post, "Keep your heads down, U.S. embassy warns Americans ahead of London Trump visit," 11 July 2018 An incoming email, for example, shows the sender's name first when the alert hits your wrist. Valentina Palladino, Ars Technica, "Garmin Vivosmart 4 review: An affordable band for easy fitness, SpO2 data," 27 Oct. 2018

Recent Examples on the Web: Verb

Lane Keeping Assist may be insufficient to alert a fatigued or distracted driver of lane drift and cannot be relied on to avoid an accident or serious injury. Popular Mechanics Editors, Popular Mechanics, "The All-New 2019 Mercedes-Benz Sprinter Is Pushing Commercial Utility Into the Future," 1 Dec. 2018 The investigation is focused on two Deutsche Bank employees, identified only by their ages, and potentially others who are suspected of helping their clients create offshore accounts and failing to alert the authorities of suspicious transactions. Emily Stewart, Vox, "Deutsche Bank’s German office raids (apparently) have nothing to do with Trump," 30 Nov. 2018 Auto makers are increasingly outfitting base-model vehicles with advanced safety gear that use cameras and radars to alert drivers to potential hazards. Adrienne Roberts, WSJ, "U.S. Road Deaths Fell in 2017," 3 Oct. 2018 Air quality alerts are issued by the National Oceanic and Atmospheric Administration (NOAA), in partnership with the Environmental Protection Agency (EPA), in order to alert people that they’re being exposed to unhealthy levels of air pollution. Korin Miller, SELF, "How to Stay Safe When Your City’s Air Quality Is Dangerous," 21 Aug. 2018 This new off-the-shelf camera system Uber is integrating will instead detect distracted driving in real time, log it into the system automatically, and then make a noise to alert the driver to pay attention. Johana Bhuiyan, Recode, "Months after a self-driving crash, Uber is being slower and more deliberate as it gets back on public roads to test its technology," 24 July 2018 During the trip, another Steamship Authority bus driver saw smoke coming from the back of the first vehicle and alerted its driver, who turned back to the Palmer Avenue lot. John Hilliard, BostonGlobe.com, "Burning Steamship Authority bus damages cars in Falmouth parking lot," 7 July 2018 But the system is not designed to alert the driver. NBC News, "Backup driver in deadly autonomous crash was streaming TV show, police report says," 23 June 2018 Toyota, for example, has a system of three audible signals outside the car, and one inside, to alert drivers getting out of a vehicle that the motor is still running. Anchorage Daily News, "Keyless cars are convenient, but can lead to a deadly error," 14 May 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, Noun, and Verb

Italian all'erta, on the watch, literally, on the height

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Dictionary Entries near alert

Aleppo stone

alerce

alerion

alert

-ales

alesan

Alessandria

Statistics for alert

Last Updated

8 Jan 2019

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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More from Merriam-Webster on alert

Rhyming Dictionary: Words that rhyme with alert

Thesaurus: All synonyms and antonyms for alert

Spanish Central: Translation of alert

Nglish: Translation of alert for Spanish Speakers

Britannica English: Translation of alert for Arabic Speakers

Comments on alert

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