alert - definition in the American English Dictionary - Cambridge Dictionaries Online (US)

Cambridge Dictionaries online Cambridge Dictionaries online

The most popular online dictionary and thesaurus for learners of English

English definition of “alert”

See all translations


adjective  us   /əˈlɜrt/
quick to see, understand, and act in a particular situation: When you’re driving, you must stay alert. We had to be alert to any danger signs in the economy.


noun [C/U]  us   /əˈlɜrt/
a warning to people to get ready to deal with something dangerous: [U] The police were on the alert for (= watching carefully for) any sign of trouble.
verb [T]  us   /əˈlɜrt/
The auto company mailed letters to owners of that model car, alerting them of safety risks.
(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

Definitions of “alert” in other dictionaries

Word of the Day

cost/charge the earth

to cost, charge, etc. a lot of money

Word of the Day

The language of elections

by Liz Walter,
April 22, 2015
On May 7th, citizens of the UK will be going to the polls (having an election) to decide who will form the next government. This kind of election is known as a general election. The country is divided into 650 areas, called constituencies. Each constituency elects a member of parliament (MP) to

Read More 

dumbwalking noun

April 20, 2015
walking slowly, without paying attention to the world around you because you are consulting a smartphone He told me dumbwalking probably wouldn’t be a long-term problem.

Read More