red alert

noun

Definition of red alertnext
as in watch
the state of being constantly attentive and responsive to signs of opportunity, activity, or danger the paparazzi were on red alert for sightings of the hot new Hollywood couple

Synonyms & Similar Words

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Antonyms & Near Antonyms

Example Sentences

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.
Recent Examples of red alert Italy’s Health Ministry placed all 27 cities monitored under its national heat surveillance system on red alert Thursday — the first time this year the entire network has been under the highest warning level simultaneously. — ABC News, 6 Aug. 2026 Sunday’s stage through the Massif Central was won by Mathieu van der Poel, out-sprinting a small breakaway group, having been shortened by 30km due to a ‘red alert’ heatwave in the region. — Jacob Whitehead, New York Times, 13 July 2026 The center on Saturday also issued the first red alert for rainstorms of the year, according to state broadcaster CCTV. — Los Angeles Times, 11 July 2026 Three-quarters of France, encompassing tens of millions of people, was put under a red alert for extreme heat on Thursday and Friday as the mercury topped 40 C (104 F) in some locations, including in Paris. — Kirsten Grieshaber, Fortune, 27 June 2026 See All Example Sentences for red alert
Recent Examples of Synonyms for red alert
  1. watch
  2. watchfulness
  3. alert
  4. alertness
  5. vigilance
Noun
  • Citi adds a positive watch on SpaceX The firm said SpaceX is firing on all cylinders following earnings.
    — Michael Bloom, CNBC, 21 Oct. 2026
  • Altogether 228,000 additional Swiss watches were exported in September versus August.
    — Jennifer Weil, Footwear News, 20 Oct. 2026
Definition of watch
Noun
  • Hechinger, all raw nerve and watchfulness, announces himself as a star.
    — Clayton Davis, Variety, 5 Sep. 2026
  • The multiple heads can be said to represent divine watchfulness of the world and devotees.
    — Charles Preston, Encyclopedia Britannica, 28 Aug. 2026
Definition of watchfulness
Noun
  • The alert is for Western San Gabriel Mountains and Highway 14 Corridor, Eastern San Gabriel Mountains, Western Antelope Valley Foothills, Eastern Antelope Valley Foothills and Antelope Valley.
    — CA Weather Bot, Sacbee.com, 24 Oct. 2026
  • The warning signs, and state response In May, the North American Electric Reliability Corporation issued a Level 3 alert, its most serious, warning that sudden swings in data center demand threaten the stability of the grid.
    — Neil Chatterjee, Fortune, 23 Oct. 2026
Definition of alert
Noun
  • Ellen displays intimacy with Lara in front of Ruby; Lara withholds and then offers attention; Ruby watches with envy, desire, and the alertness of a guest who cannot tell whether she is being welcomed or appraised.
    — Literary Hub, Literary Hub, 24 Sep. 2026
  • Kratom products contain chemicals that can increase alertness, physical energy, and talkativeness.
    — Ivan Pereira, ABC News, 23 Sep. 2026
Definition of alertness
Noun
  • The advisories urged Americans to exercise vigilance and prepare for possible flight cancellations, airspace closures and other travel disruptions.
    — Olivia Gazis, CBS News, 20 Oct. 2026
  • This method works only as long as employees exercise constant vigilance—over the machines, themselves, and one another.
    — Gideon Lewis-Kraus, New Yorker, 19 Oct. 2026
Definition of vigilance

Browse Nearby Words

redacts
red alert
red-blooded
See all Nearby Words

Cite this Entry

“Red alert.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/red%20alert. Accessed 26 Oct. 2026.

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