red alert

noun

Synonyms of red alertnext
: the final stage of alert in which enemy attack appears imminent
broadly : a state of alert brought on by impending danger

Synonyms of red alert

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Examples of red alert in a Sentence

The troops have been put on red alert. the paparazzi were on red alert for sightings of the hot new Hollywood couple
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Red heat wave alerts across Italy Italy on Monday issued heat wave red alerts for 12 cities. — Makini Brice, USA Today, 23 June 2026 In Europe, a record-breaking heatwave has prompted red alerts across the continent. — Lim Hui Jie,leonie Kidd, CNBC, 25 June 2026 The red alert is the highest level of the national heatwave plan, reserved for an exceptional heatwave. — Laure Guilbault, Vogue, 23 June 2026 Areas of France, Britain, Austria and the Netherlands have issued red alerts or warnings on account of the extreme heat. — Los Angeles Times, 6 July 2026 See All Example Sentences for red alert

Word History

First Known Use

1941, in the meaning defined above

Time Traveler
The first known use of red alert was in 1941

Browse Nearby Words

red-alder family
red alert
red alga
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Cite this Entry

“Red alert.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/red%20alert. Accessed 7 Jul. 2026.

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