red alert

noun

1. (in military or civilian defense) the most urgent form of alert, signaling that an enemy attack is believed to be imminent.

2. the signal or alarm sounded for this alert.

3. a signal or warning that a critical situation is developing or has occurred.

4. the period during which a state of crisis or danger is declared to exist.

Word History and Origins

Origin of red alert¹

First recorded in 1960–65

Example Sentences

Understandably therefore, the officials are on red alert, desperate to ensure any dangerous tackles or collisions don't slip through the net.

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Mexico put out a global Interpol “red alert” seeking Zhang’s capture.

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The highest red alert has been declared in the coastal province by Spain's national weather agency AEMET.

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Fresh floods struck Spain on Sunday as part of the northeastern Catalonia region faced a red alert for torrential rain, a day after downpours unleashed travel chaos on the Mediterranean island of Ibiza.

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Spanish media report that emergency services issued a telephone alert to those covered by the red alert, with people urged to avoid flood-prone areas, including low-lying ground and basements.

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