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

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

The newest watch can detect hard falls and alert emergency contacts. Dan Gallagher, WSJ, "It Is Prime Time for Smartwatches," 6 Mar. 2019 In surveillance video, Martinez appeared to alert customers to her attacker. Katherine Lam, Fox News, "Jogger stabbed to death in Washington, DC, collapses in takeout restaurant as attacker flees, cops say," 19 Sep. 2018 Croatia had opportunities to extend their lead with good chances inside the box, however alert goalkeeping from Schmeichel kept the scores down and helped the game to develop some sort of rhythm after a crazy opening. SI.com, "Croatia 1-1 Denmark (3-2 Pens): Ivan Rakitić Breaks Danish Hearts Despite Kasper Schmeichel Heroics," 2 July 2018 The Florida Department of Law Enforcement put out the alert Saturday morning. Monique O. Madan, miamiherald, "These three children have gone missing together. Police need your help.," 30 June 2018 According to Everyday Health, meditation can improve concentration, reduce stress, prevent cognitive decline, and keep your brain healthy and alert as you age. Jessica Leigh Mattern, Woman's Day, "30 Fun Things to Do By Yourself in Your Lifetime," 3 Jan. 2019 The students also reported feeling less sleepy and more alert. Angela Chen, The Verge, "Why we might want the school day to start later," 12 Dec. 2018 The result is military personnel more alert, focused, and better able to do their jobs. Kyle Mizokami, Popular Mechanics, "A New Electronic Device Could Cure the Military's Big Motion Sickness Problem," 22 Nov. 2018 Hence, if software can drive as well as the average sober, alert human driver, its widespread use would save thousands of lives per year. Timothy B. Lee, Ars Technica, "Car crashes killed 37,133 people in the US in 2017," 3 Oct. 2018

Recent Examples on the Web: Noun

Getting the alerts also helped them in the interview process. Liz Bentley, Marie Claire, "My Boss Follows Me on Instagram — What Do I Do?," 1 Apr. 2019 In both California and Greece, most people heard about the fire not from government emergency-alert systems but from neighbors or friends. Costas Synolakis, WSJ, "Lessons From the Paradise Fire," 18 Nov. 2018 The alert and the graphic deaths weren't related, but several media outlets linked the travel warning to the recent violence. Sebastian Modak, Condé Nast Traveler, "What the Changes to Mexico's Travel Advisory Really Mean," 27 Aug. 2018 According to the alert, police responded in minutes but weren’t able to find the Hyundai, though investigators later identified one matching its description on surveillance footage. Jeff Weiner, OrlandoSentinel.com, "Man performed 'sex act' in front of 2 women at UCF campus, police say," 10 July 2018 Earlier this year, an update in the Jacquard platform introduced a handful of other functions, like support for ride-sharing alerts and pin drops on a map to save locations. 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 And sign up for email or text alerts on your accounts so you're notified about major activity, purchases, withdrawals, etc. Teresa Dixon Murray, cleveland.com, "Malley's Chocolates' website hacked, 3,400 online customers' card information breached," 10 May 2018 Just subscribe here: Get breaking news alerts on Apple News Don’t want to keep hitting the refresh button? Dan Frommer, Recode, "Code Commerce, our summit on the future of retail, is almost here. Here’s how to follow along.," 14 Sep. 2018 The throttle and gearbox are plenty alert and when commanded the six will quietly pull its heart out. Dan Neil, WSJ, "2019 Mercedes-Benz CLS: A Move Toward Electrification," 3 Aug. 2018

Recent Examples on the Web: Verb

The Roman Catholic Diocese of Covington said in a statement late Tuesday that local police alerted them a protest was planned. John Minchillo, The Seattle Times, "Boys school shuts down amid fallout over Washington videos," 23 Jan. 2019 Not coincidentally, Baser says one of the focuses for his team is coming up with a faster and clearer way of alerting users of privacy mishaps. Kurt Wagner, Recode, "Facebook still hasn’t launched a big privacy feature that Mark Zuckerberg promised more than seven months ago," 17 Dec. 2018 The couple alerted police in the area, who made an attempt to retrieve the ring but couldn’t find it in the dark, the NYPD said. Charles Passy, WSJ, "NYPD to the Rescue in Case of the Lost Engagement Ring," 2 Dec. 2018 But this could be one of them: A new feature on the personal-safety app Noonlight aims to help victims of car crashes and other accidents by automatically alerting emergency services the moment an accident happens, The Washington Post reported. Suzannah Weiss, Teen Vogue, "The Noonlight App Calls 911 When It Detects You’ve Been in an Accident," 2 Oct. 2018 Binns said relatives alerted police to concerns that Reed was being scammed by someone using a false identity to woo her. Jonathan Drew, Fox News, "Police: Online love scam leads investigators to killing plot," 14 Aug. 2018 Fox said a field guide alerted the Anti-Poaching Unit that there appeared to be human remains and poaching weapons near the lions earlier this week. Gina Martinez, Time, "A Pride of Lions Killed and Ate a Group of Rhino Poachers Who Broke Into a Wildlife Reserve," 5 July 2018 In his letter to parents and students, which was sent on Wednesday, Mr. Conrad said that after the yearbook was published last week, a student, who had researched the Holocaust, alerted the school to the quote’s origins. Mihir Zaveri, New York Times, "Massachusetts High School Apologizes After Nazi Quote Is Printed in Yearbook," 16 June 2018 Police say administrators at Lewis and Clark Elementary School alerted a campus security officer on Thursday morning to request a welfare check at the home of two absent students. Jeff Truesdell, PEOPLE.com, "N.D. Mom Apparently Kills Herself and Three Children After Complaining of Financial Woes," 4 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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Learn More about alert

Dictionary Entries near alert

Aleppo stone

alerce

alerion

alert

-ales

alesan

Alessandria

Statistics for alert

Last Updated

2 Apr 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 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.
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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