alert Meaning in the Cambridge English Dictionary
Cambridge Dictionaries online Cambridge Dictionaries online

The most popular online dictionary and thesaurus for learners of English

Meaning of “alert” in the English Dictionary

"alert" in British English

See all translations

alertadjective

uk   /əˈlɜːt/  us   /-ˈlɝːt/
C1 quick to ​see, ​understand, and ​act in a ​particularsituation: I'm not ​feeling very alert today - not enough ​sleep last ​night! A ​couple of alert ​readerspostedcomments on the ​websitepointing out the ​mistake. Parents should be alert tosuddenchanges in children's ​behaviour.
More examples
alertness
noun [U] uk   us   /-nəs/

alertnoun [C or U]

uk   /əˈlɜːt/  us   /-ˈlɝːt/
C1 a ​warning to ​people to be ​prepared to ​deal with something ​dangerous: a bomb alert The ​army was put on (​full) alert as the ​peacetalksbegan to ​fail. The ​public were ​warned to be on the alert for (= ​watchingcarefully for)suspiciouspackages.

alertverb [T]

uk   /əˈlɜːt/  us   /-ˈlɝːt/
C2 to ​warn someone of a ​possiblydangeroussituation: An ​anonymousletter alerted ​police to the ​possibility of a ​terroristattack at the ​airport.
More examples
(Definition of alert from the Cambridge Advanced Learner’s Dictionary & Thesaurus © Cambridge University Press)

"alert" in American English

See all translations

alertadjective

 us   /əˈlɜrt/
quick to ​see, ​understand, and ​act in a ​particularsituation: When you’re ​driving, you must ​stay alert. We had to be alert to any ​dangersigns in the ​economy.

alertnoun [C/U]

 us   /əˈlɜrt/
a ​warning to ​people to get ​ready to ​deal with something ​dangerous: [U] The ​police were on the alert for (= ​watchingcarefully for) any ​sign of ​trouble.
alert
verb [T]  us   /əˈlɜrt/
The ​autocompany mailed ​letters to owners of that ​modelcar, alerting them of ​safetyrisks.
(Definition of alert from the Cambridge Academic Content Dictionary © Cambridge University Press)
What is the pronunciation of alert?
Add Cambridge dictionaries to your browser to your website

More meanings of “alert”

Word of the Day

harvest

to pick and collect crops, or to collect plants, animals, or fish to eat

Word of the Day

In London but at the station: prepositions for talking about travel
In London but at the station: prepositions for talking about travel
by Liz Walter,
September 02, 2015
Several readers have asked for information on prepositions, so I will start with a blog post that looks at an area where they are really important: travel. The first thing to remember is that we use to (and not ‘in’) after the verb go: We are going to London. I went to

Read More 

parklet noun
parklet noun
August 31, 2015
a public outdoor space that may be associated with a local business but where anyone can sit Pop-up cafes in NY are what’s actually called parklets in many other places around the country.

Read More