alert

1 of 3

adjective

ə-ˈlərt How to pronounce alert (audio)
Synonyms of alertnext
1
a
: 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
alertly adverb
alertness noun

alert

2 of 3

noun

1
: a state of careful watching and readiness especially for danger or opportunity
on 24-hour alert
2
a
: 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

alert

3 of 3

verb

alerted; alerting; alerts

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
Phrases
on the alert
: looking for or expecting something (such as danger or an opportunity)
Drivers need to be on the alert for icy conditions.
always on the alert for a good bargain

Synonyms

Adjective

Noun

Verb

See all Synonyms & Antonyms in Thesaurus 
Choose the Right Synonym for alert

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.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Adjective
Bucks that seem alert and nervous — look for twitchy ears and a constantly bobbing head — are more likely to detect you movement and are also more likely to duck arrows. —Alex Robinson, Outdoor Life, 6 Nov. 2024 Other cultures took naps during the day to adapt to intense midday temperatures or feel more alert during nighttime dangers. —Carley Millhone, Health, 31 Oct. 2024
Noun
However, as the region faces its second day of severe weather in a row, residents remain on alert while the weather service continues its investigations. —Thomas G. Moukawsher, Newsweek, 5 Nov. 2024 But the insurrection put the American public on high alert. —Jenna Bednar, Foreign Affairs, 5 Nov. 2024
Verb
His ability to nearly propel the Bucs past the Chiefs, and do so without his top wide receivers, alerted the 49ers not to take him or the Bucs lightly. —Cam Inman, The Mercury News, 9 Nov. 2024 Mills has employed one clever trick over the years for getting deer to stop without alerting them: scent balls. —Alex Robinson, Outdoor Life, 6 Nov. 2024 See all Example Sentences for alert 

Word History

Etymology

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

First Known Use

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

Time Traveler
The first known use of alert was in 1618

Phrases Containing alert

Dictionary Entries Near alert

alerion

alert

-ales

See More Nearby Entries 

Cite this Entry

“Alert.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/alert. Accessed 22 Nov. 2024.

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Kids Definition

alert

1 of 3 adjective
ə-ˈlərt How to pronounce alert (audio)
1
a
: being watchful and ready to meet danger
b
: quick to understand and act
2
: active sense 3, brisk
alertly adverb
alertness noun

alert

2 of 3 noun
1
: a signal of danger
2
: the period during which an alert is in effect

alert

3 of 3 verb
: to call to a state of readiness : warn

More from Merriam-Webster on alert

Nglish: Translation of alert for Spanish Speakers

Britannica English: Translation of alert for Arabic Speakers

Last Updated: - Updated example sentences
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