red alert
Americannoun
-
(in military or civilian defense) the most urgent form of alert, signaling that an enemy attack is believed to be imminent.
-
the signal or alarm sounded for this alert.
-
a signal or warning that a critical situation is developing or has occurred.
-
the period during which a state of crisis or danger is declared to exist.
Etymology
Origin of red alert
First recorded in 1960–65
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
Scientists said in a study released Friday that climate change was "unequivocally" responsible for the heat that broke records in Britain, France, Spain and Switzerland, while the Netherlands issued its first-ever red alert over heat.
From Barron's ● Jun. 26, 2026
A red alert level for "extreme thermal stress" has been extended in the grand duchy until Saturday night.
From BBC ● Jun. 25, 2026
The list of cities issued with a red alert warning is long and set to grow on Wednesday, with the most sweltering spots in the centre and north of the country.
From BBC ● Jun. 23, 2026
It comes as England braces for temperatures of up to 40C, with the Met Office issuing a rare red alert set to come into force on Wednesday.
From BBC ● Jun. 23, 2026
Every time the phone rang his body went to red alert.
From "Small Steps" by Louis Sachar
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
