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 The two toddlers were alert when the agents made contact with them, according to CBP. Christopher Brito, CBS News, "Video shows alleged smugglers dropping 2 children over 14-foot border fence into U.S.," 2 Apr. 2021 The weather service issued a dense fog advisory through 11 a.m. Thursday and warned drivers to be alert and keep headlights on low beam. Mckenna Oxenden, baltimoresun.com, "Baltimore weather: Wednesday was the region’s rainiest March 24, breaking 1989 record," 25 Mar. 2021 Late Friday evening, police said Wittstruck was alert and expected to undergo surgery. Michael Ruiz, Fox News, "Omaha police officer recovering after getting shot twice in head, authorities say," 14 Mar. 2021 Kids who were alert, bright-eyed and attentive during our therapy sessions a year ago are now often listless, lethargic and sometimes literally in bed. John Duffy, CNN, "Many teens live online, alone. Here's how to stay connected in the pandemic," 4 Mar. 2021 Police said Woods was alert as firefighters pried open the front windshield to get him out. Stefanie Dazio And Doug Ferguson, chicagotribune.com, "Tiger Woods faces a difficult recovery after his SUV flipped several times in crash: ‘Very fortunate (he) was able to come out of this alive’," 24 Feb. 2021 Police said Woods was alert as firefighters pried open the front windshield to get him out. Stefanie Dazio And Doug Ferguson, Chron, "Tiger Woods seriously injured in crash on steep LA-area road," 24 Feb. 2021 Police said Woods was alert as firefighters pried open the front windshield to get him out. Stefanie Dazio, Doug Ferguson, Anchorage Daily News, "Lucky to be alive after SUV crash, Tiger Woods faces a difficult recovery," 24 Feb. 2021 Police said Woods was alert as firefighters pried open the front windshield to get him out. Mark Heim | Mheim@al.com, al, "Tiger Woods awake, responsive, recovering from ‘open fractures’ after accident," 24 Feb. 2021 Recent Examples on the Web: Noun The gunman and police exchanged gunfire, police said, before the suspect was arrested just before 3:30 p.m. Boulder police issued an alert about the shooting just before 5 p.m., telling people to avoid the area near the grocery store. Rick Rouan, USA TODAY, "Fact check: Colorado mass shooting is not a 'false flag' as conspiracy theory claims," 23 Mar. 2021 State Attorney General Dana Nessel issued a consumer alert Wednesday, urging Michiganders to be aware of a new COVID-19-related scam identified in Bay County. Kristen Jordan Shamus, Detroit Free Press, "Michigan attorney general issues consumer alert about COVID-19 scams," 17 Mar. 2021 The Food and Drug Administration issued the alert to Friday for health facilities using Roche’s cobas test for coronavirus and seasonal flu. BostonGlobe.com, "Hundreds of Tesla workers tested positive for virus after Musk reopened plant, data show," 13 Mar. 2021 UDOT Traffic issued a weather alert for the weekend warning that snow will impact Utah roads, especially in eastern Utah mountains. Sara Tabin, The Salt Lake Tribune, "Snow breaks records in St. George, slows traffic around the state," 13 Mar. 2021 The Cybersecurity Infrastructure and Security Agency issued an urgent alert on the hack last Wednesday and National Security Advisor Jake Sullivan tweeted about it Thursday evening. Frank Bajak, Time, "A Microsoft Server Hack Has Victims Scrambling to Stop Intruders," 9 Mar. 2021 The Alabama Law Enforcement Agency has issued an emergency missing child alert for a teenage girl from Limestone County. William Thornton | Wthornton@al.com, al, "Emergency missing child alert issued for 13-year-old north Alabama girl," 9 Mar. 2021 The Cybersecurity Infrastructure and Security Agency issued an urgent alert on the hack last Wednesday and National Security Advisor Jake Sullivan tweeted about it Thursday evening. Frank Bajak, Star Tribune, "Microsoft server hack has victims hustling to stop intruders," 8 Mar. 2021 New Zealand authorities have issued a tsunami alert for sections of the north island, ordering people in several sections of the island to evacuate immediately. Los Angeles Times, "Tsunami watch ordered in Hawaii after 8.1 New Zealand quake; impact on California under review," 4 Mar. 2021 Recent Examples on the Web: Verb The idea was to alert public safety officials about these events more quickly. Bethany Rodgers, The Salt Lake Tribune, "State auditors find that Banjo oversold its surveillance tech to the Utah attorney general’s office," 30 Mar. 2021 His gradual accumulation of guns went undetected because federal law doesn't require licensed gun dealers to alert the government about rifle purchases. Michael R. Sisak, Chron, "Mass shooters exploited gun laws, loopholes before carnage," 25 Mar. 2021 David Alexander, ProSlide senior vice president of corporate affairs, said in the theme park industry, park operators typically alert ride suppliers promptly about incidents to ensure guests’ safety. Gabrielle Russon, orlandosentinel.com, "Accidents on Universal Orlando’s Volcano Bay water slides bring 73 injury claims, court documents say," 26 Aug. 2020 Under House Bill 12, the state would study the costs of implementing this system, which would alert Texans about impending disasters and extreme weather events. James Barragán, Dallas News, "Texas House Speaker Dade Phelan announces electricity priority bills to tackle winter storm outages," 8 Mar. 2021 The change has drawn criticism from a former top ICE official, who said it’s dangerous not to use every avenue to alert the public about fugitive illegals. Paul Bedard, Washington Examiner, "ICE suspends its 'Most Wanted' alert for fugitive aliens, raising safety concerns," 2 Mar. 2021 Members, who are grouped by their immediate neighborhoods, use the app to report bird sightings and alert others about missing pets. Washington Post, "D.C.’s 911 center saw a spike in suspicious-activity calls after Capitol riot," 19 Feb. 2021 DHS’s Office of Intelligence and Analysis was one of the federal agencies that failed to alert federal law enforcement agencies to plans by pro-Trump groups to storm the U.S. Capitol and attempt to prevent a presidential transition. Washington Post, "DHS announces $77 million in grant funding to combat domestic terror and extremism," 25 Feb. 2021 The Amber Alert system started in Texas in 1996, after the abduction and brutal murder of 9-year-old Amber Hagerman, as a way to use broadcasting systems to alert the public to child abduction cases. Editorial Board, Star Tribune, "A citizen cared, and a child was found," 8 Feb. 2021

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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Statistics for alert

Last Updated

6 Apr 2021

Cite this Entry

“Alert.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/alert. Accessed 17 Apr. 2021.

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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.

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

Thesaurus: All synonyms and antonyms for alert

Nglish: Translation of alert for Spanish Speakers

Britannica English: Translation of alert for Arabic Speakers

Comments on alert

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