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 volcanology agency has placed Taal and outlying cities and towns at alert level 4, the second-highest warning, indicating a more dangerous explosive eruption is possible within hours or days. Aaron Favila And Jim Gomez, SFChronicle.com, "Philippine government bars residents from returning to volcano island," 19 Jan. 2020 The Philippine Institute of Volcanology and Seismology raised the alert level to four out of five, warning that another hazardous eruption could take place anytime. Adrianna Rodriguez, USA TODAY, "Heartbreaking photos show dogs and horses being rescued after Taal volcano eruption," 16 Jan. 2020 The alert level since the eruption began Sunday has been 4, indicating a hazardous eruption is possible in hours to days. Joeal Calupitan, Anchorage Daily News, "Philippine volcano spews lava a half-mile high and coats towns in heavy ash," 14 Jan. 2020 The agency raised the alert level to four on a scale of five, as researchers have recorded hundreds of small earthquakes and huge lava fountains near the main crater. Michael J. Coren, Quartz, "The eruption of the Taal volcano isn’t affecting the global climate just yet," 14 Jan. 2020 The institute raised the alert level to four on a scale of five on Sunday. Jason Gutierrez, New York Times, "Desperate Residents Ignore Dangers of Philippine Volcano and Return Home," 13 Jan. 2020 The institute raised the alert level to 4 on a scale of 5 Sunday. Jason Gutierrez, BostonGlobe.com, "Desperate residents ignore dangers of Philippine volcano and return home," 13 Jan. 2020 Three weeks earlier, New Zealand’s seismic monitoring agency GeoNet had raised the alert level on the island from 1 to 2, on a scale where 5 is a major eruption. Nick Perry, Twin Cities, "Rescuer describes horror of New Zealand’s silent eruption; 16 believed killed," 14 Dec. 2019 Many people were questioning why tourists were allowed to visit the island after seismic monitoring experts raised the volcano’s alert level last month. Paige Fry, chicagotribune.com, "Family from Chicago listed among the missing after volcano erupts on New Zealand island," 11 Dec. 2019 Recent Examples on the Web: Noun Blind-spot monitoring and rear cross-traffic alert are optional. Eric Stafford, Car and Driver, "Hyundai's Subcompact Venue Speaks to the People," 20 Jan. 2020 But two new and unexpected volumes—expertly edited and with wonderfully informative footnotes by the poet and scholar Saskia Hamilton, who also provides an alert and balanced introduction to each—have now been published. Helen Vendler, Harper's magazine, "Dearest Lizzie," 20 Jan. 2020 Make sure you're notified about new horoscopes by switching on event alerts! Venus Australis, refinery29.com, "Your Horoscope This Week," 13 Jan. 2020 This alert has been widely cited, and politicians who have invoked it have been repeatedly fact-checked. Naomi Oreskes, Scientific American, "Don’t Fact-Check Scientific Judgment Calls," 13 Jan. 2020 The coast was under a National Weather Service high surf warning, the highest alert for waves, and was also experiencing unusually high tides known as king tides. Dennis Romero And Linda Takahashi, NBC News, "Girl dead, 4-year-old boy missing, after trio swept to sea in Oregon," 12 Jan. 2020 Have a local news source (that provides live broadcasts) as well as other methods of receiving alerts on Saturday. Anna Beahm | Abeahm@al.com, al, "Tuscaloosa preps for the worst ahead of Saturday storms," 10 Jan. 2020 The aesthetics are basically identical: Both rely on character actors decked out in chunky exploration suits, fumbling their way through postindustrial corridors while contending with loudly bleeping alerts from stern computer voices. David Sims, The Atlantic, "Underwater Entertains but Doesn’t Have Much Depth," 9 Jan. 2020 Nothing, not a scrap of fur, though the road seemed to hum, alert as skin to the touch. D. Nurkse, The New Yorker, "The Body," 6 Jan. 2020 Recent Examples on the Web: Verb Weidel said a witness saw the suspect fleeing in a car and alerted police to the license plate number. Ryan Tarinelli And Michael R. Sisak, SFChronicle.com, "5 stabbed at rabbi’s New York home amid rising attacks on Jews," 29 Dec. 2019 Police said the stabbings happened at around 10 p.m. A witness saw the suspect fleeing in car and alerted police to license plate number, Weidel, the police chief in Ramapo, which covers Monsey, said. Arkansas Online, "5 stabbed at rabbi's house on Hanukkah; suspect in custody," 29 Dec. 2019 Once whooping cranes began showing up around the refuge’s visitor center and the two-story observation building about 200 yards (180 meters) down a trail from it, the refuge began alerting the public. Frank Sargeant, al, "Outdoors notebook: FLW Pro Circuit schedules bass tourney on Lake Martin," 24 Nov. 2019 The agent alerted local police, who promptly arrested and booked Diaz into the downtown Bakersfield jail, according to sheriff’s office records. Jason Pohl, ProPublica, "A Jail Increased Extreme Isolation to Stop Suicides. More People Killed Themselves.," 5 Nov. 2019 While footage can be used to alert police to a break-in or to secure a courtroom conviction, the most effective function of surveillance cameras is, say it again, deterrence. Wired, "In Praise of Ugly and Conspicuous Security Cameras," 22 Oct. 2019 The zoo moved Louie from his habitat and last week alerted the public that he was being monitored and treated for an unknown medical condition, executive director Pat Lampi said at the time in a statement. Zaz Hollander, Anchorage Daily News, "Lyutyik the polar bear, Alaska Zoo webcam star, has died," 15 Oct. 2019 Now, within the span of a little more than a year, more than 100 dioceses and religious orders have come forward with thousands of names — but often little other information that can be used to alert the public. Claudia Lauer And Meghan Hoyer, chicagotribune.com, "Without oversight, scores of accused priests live under the radar and commit crimes," 5 Oct. 2019 Now, within the span of a little more than a year, more than 100 dioceses and religious orders have come forward with thousands of names _ but often little other information that can be used to alert the public. NBC News, "Almost 1,700 priests and clergy accused of sex abuse are unsupervised," 4 Oct. 2019

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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Time Traveler for alert

Time Traveler

The first known use of alert was in 1618

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Statistics for alert

Last Updated

22 Jan 2020

Cite this Entry

“Alert.” The Merriam-Webster.com Dictionary, Merriam-Webster Inc., https://www.merriam-webster.com/dictionary/alertness. Accessed 24 January 2020.

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More Definitions for alert

alert

adjective
How to pronounce alert (audio)

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

Rhyming Dictionary: Words that rhyme with alert

Spanish Central: Translation of alert

Nglish: Translation of alert for Spanish Speakers

Britannica English: Translation of alert for Arabic Speakers

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