alert

[ uh-lurt ]

adjective

1. fully aware and attentive; wide-awake; keen:

   She had an alert mind.

   Synonyms: observant, wary, awake

   Antonyms: unaware

2. swift; agile; nimble.

   Synonyms: spirited, sprightly, active, quick, lively, brisk

noun

1. an attitude of vigilance, readiness, or caution, as before an expected attack.
2. a warning or alarm of an impending military attack, a storm, etc.:

   We'd just boarded the bus when the alert sounded.

3. the period during which such a warning or alarm is in effect.

verb (used with object)

1. to warn (troops, ships, etc.) to prepare for action.
2. to warn of an impending raid, attack, storm, etc.:

   The radio alerted coastal residents to prepare for the hurricane.

3. to advise or warn; cause to be on guard:

   to alert gardeners to the dangers of some pesticides.

alert

/ əˈlɜːt /

adjective

1. vigilantly attentive

   alert to the problems

2. brisk, nimble, or lively

noun

1. an alarm or warning, esp a siren warning of an air raid
2. the period during which such a warning remains in effect
3. on the alert
   on the alert
   1. on guard against danger, attack, etc
   2. watchful; ready

      on the alert for any errors

verb

1. to warn or signal (troops, police, etc) to prepare for action
2. to warn of danger, an attack, etc

Derived Forms

• aˈlertly, adverb
• aˈlertness, noun

Other Words From

• a·lertly adverb
• a·lertness noun
• hyper·a·lert adjective
• una·lerted adjective

Word History and Origins

Origin of alert¹

First recorded in 1590–1600; 1940–45 alert fordef 4; from Italian all'erta, equivalent to all ( a ) “to, on the” + erta “lookout, watchtower,” originally feminine of erto, past participle of ergere from Latin ērigere to erect

Word History and Origins

Origin of alert¹

C17: from Italian all'erta on the watch, from erta lookout post, from ergere to build up, from Latin ērigere; see erect

Idioms and Phrases

Idioms

1. on the alert, on guard against danger; in readiness; vigilant:

   The state police are on the alert for an escaped convict believed to be in the area.

More idioms and phrases containing alert

see on the alert .

Synonym Study

Alert, vigilant, watchful imply a wide-awake attitude, as of someone keenly aware of their surroundings. Alert describes a ready and prompt attentiveness together with a quick intelligence: The tourist was alert and eager to see the sights. Vigilant suggests some immediate necessity for keen, active observation, and for continuing alertness: Knowing the danger, the scout was unceasingly vigilant. Watchful suggests carefulness and preparedness: A stakeout requires watchful waiting.

Example Sentences

Minutes before an airplane hit the water, an alert would go out.

From The Daily Beast

France is on high alert this week after a series of attacks by loners.

From The Daily Beast

I also want to alert you to the broader circumstances of my incarceration.

From The Daily Beast

Spoiler Alert: Do not read if you haven't seen season five episode eight of  The Walking Dead, “Coda”

From The Daily Beast

They walk closely together, tense, and alert in their movements.

From The Daily Beast

It was Carmena, every nerve of her loyal nature on the alert to baffle this pursuer of Alessandro and Ramona.

From Project Gutenberg

Then, his hand resting on the handle of the cab-door, this expression suddenly changed to one of alert suspicion.

From Project Gutenberg

He is small, alert, brimful of jokes and of years; seventy they say, but he neither looks it nor acts it.

From Project Gutenberg

But his eyes and ears were alert, and he was the first to hear the advent of a large body of horses along the main road.

From Project Gutenberg

The almost lazy naturalness and simplicity faded gradually out of it, revealing the alert and seductive woman of the world.

From Project Gutenberg

Related Words

• alarm
• signal