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 In an alert Friday, regulators flagged reports of serious side effects and death among patients taking hydroxychloroquine and the related drug chloroquine. Tucker Reals, CBS News, "Coronavirus updates: America's death toll passes 50,000," 24 Apr. 2020 Institutions and regular web users are always on alert about avoiding errant clicks and downloads online that could lead their devices to be infected with malware. Lily Hay Newman, Wired, "Sneaky Zero-Click Attacks Are a Hidden Menace," 24 Apr. 2020 However, an oxygen-monitoring device called a pulse oximeter can help to detect low oxygen levels and alert people to seek early medical care, says Dr. Patel. Claire Gillespie, Health.com, "'Silent Hypoxia' Is Making Some Coronavirus Patients Critically Ill—Here's Why It's So Dangerous," 23 Apr. 2020 Some Asian countries have used digital surveillance to track patients and alert contacts. Brian Chasnoff, ExpressNews.com, "Leaders mull reopening as experts warn of coming coronavirus waves," 23 Apr. 2020 The New York City Department of Health put out an alert Wednesday warning about false negatives and false positives for antibody tests. NBC News, "What we can (and can't) take away from New York's antibody testing results," 23 Apr. 2020 Police officials have generated some backlash from victims families for not issuing the alert via mobile phone, TV and radio. Paula Newton And Theresa Waldrop, CNN, "Canadian police failed to issue timely public alert about Nova Scotia gunman," 22 Apr. 2020 Coronabonds would serialize the reward (and mutual debts) of a Union where anyone can place their social politics on the tab of more fiscally alert states. Peter Rough, National Review, "The European Union Needs More National Flexibility," 22 Apr. 2020 Babies are most alert during the first couple hours of life and will instinctively begin to root and try to suckle. New York Times, "How to Breastfeed During the First 2 Weeks of Life," 18 Apr. 2020 Recent Examples on the Web: Noun British Prime Minister Boris Johnson is expected to launch a new alert system ranking the coronavirus threat level from 1 to 5 in an address to the United Kingdom on Sunday evening, according to reports. Fox News, "UK’s Boris Johnson to unveil new coronavirus lockdown rules, including controversial ‘stay alert’ slogan," 10 May 2020 The town had a fire evacuation plan and an emergency alert system (albeit one that reached only a fraction of residents) and regularly ran emergency rehearsal drills. Rachel Monroe, New York Times, "How Paradise Went Up in Flames," 5 May 2020 Satrom listened as Chief Thompson encouraged him to put the National Guard on alert. Paula Schleis, cincinnati.com, "Making the call: Why Kent's mayor asked the governor to send the Guard to Kent State," 1 May 2020 That distinction has put government watchdogs on alert. Tom Benning, Dallas News, "Car dealership owned by Texas Rep. Roger Williams received loan through coronavirus relief fund for small businesses," 1 May 2020 Previously, the country was under a Level 4 alert, which meant people had to stay home except for essential travel like going to the supermarket. Alison Fox, Travel + Leisure, "New Zealand Allows Contactless Businesses, Schools to Reopen As Coronavirus Cases Decrease (Video)," 30 Apr. 2020 Salt Lake City: State officials started using an emergency alert system Friday to send text messages to drivers entering the state, asking them to report any virus symptoms and a recent travel history. USA TODAY, "Holy water drop, foster pet boom, ‘super spreader’: News from around our 50 states," 14 Apr. 2020 Dallas, Abilene, Austin and surrounding areas should be on alert. Jeff Berardelli, CBS News, "Easter weekend could see the most dangerous weather outbreak yet this season," 11 Apr. 2020 For years, Wisconsin hospitals have used an online alert system to advise each other of their capacity and their status. Guy Boulton, Milwaukee Journal Sentinel, "Some hospitals are hit hard by coronavirus patients, others are not. But officials won't share data, leaving residents in the dark.," 10 Apr. 2020 Recent Examples on the Web: Verb In some cases, black holes can influence the orbits of nearby objects, alerting astronomers to their presence. Jennifer Leman, Popular Mechanics, "This Is the Closest Black Hole We've Ever Discovered," 7 May 2020 Cytokines play a major role in regulating the human immune system, generally helping the body fight off infection and alerting to any problems. Emily Bamforth, cleveland, "‘Cytokine storms:' Why doctors are exploring extreme inflammatory response in severe coronavirus patients," 6 May 2020 The app alerts users who may have come in contact with people later found to be positive for COVID-19 or deemed to be at high risk. NBC News, "Malaysia rounds up migrants to contain virus, U.N. warns of detention risks," 2 May 2020 The idea is that if someone becomes infected with Covid-19, anyone who that person may have exposed can be alerted or found. Amrita Khalid, Quartz, "Digital privacy is being threatened as governments attempt to stop coronavirus," 2 May 2020 In 2003, the missing persons case of Mary Day was quickly becoming a homicide investigation – with police facing the grim task of digging in the dirt where the cadaver dogs alerted. Correspondent Maureen Maher, CBS News, "Could a suspected murder victim — back from the dead — really be an impostor?," 2 May 2020 Apple and Google said the underlying software would depend on local health agencies developing their own apps and alerting people to download and use them. Craig Timberg, BostonGlobe.com, "Most Americans are not willing or able to use an app tracking coronavirus infections," 29 Apr. 2020 If one of these people were later confirmed to have contracted coronavirus, the app would alert everyone with whom their phone had made contact, prompting them to self-isolate for two weeks. Cailey Rizzo, Travel + Leisure, "Apple and Google's Coronavirus-tracing Platform Will Alert Users If They've Encountered Someone Infected," 27 Apr. 2020 This directive is strictly enforced with the use of a GPS tracking app that alerts public health officials if the sick person leaves home. Joseph Osmundson, The New Republic, "My Life in Sero-Surveillance," 24 Apr. 2020

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

29 Apr 2020

Cite this Entry

“Alert.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/alert. Accessed 25 May. 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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