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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
  • FanDuel is giving you a chance to get in on the milestone watch with $250 in bonus bets when wagering $5+ each day for five days.
    — OutKick, FOXNews.com, 23 Sep. 2026
  • Luxury items have already proved themselves for Christie’s, where watches, jewelry, handbags, and wine can provide a relatively familiar way into an institution that can otherwise appear forbidding.
    — Daniel Cassady, ARTnews.com, 23 Sep. 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 federal prosecutors who convicted Diamantis said the government is determining what happened, including how someone subject to a travel alert could fly to Europe undetected.
    — Edmund H. Mahony, Hartford Courant, 18 Sep. 2026
  • TxDOT had been sending alerts about the closure to phones in the area.
    — Steven Rosenbaum, CBS News, 18 Sep. 2026
Definition of alert
Noun
  • This clock determines your body’s daily cycle of sleep and alertness—the circadian rhythm.
    — JD Shadel, Condé Nast Traveler, 22 Sep. 2026
  • Nicotine acts on many of the same nicotinic acetylcholine receptors that normally respond to acetylcholine, temporarily increasing alertness, attention and arousal.
    — Hasmeena Kathuria, The Conversation, 22 Sep. 2026
Definition of alertness
Noun
  • Kaepernick’s vigilance did, however, force us to consider the painful and problematic relationship between law enforcement and people of color.
    — Mike Jones, New York Times, 15 Sep. 2026
  • Finally, consider that the movement to protect kids from these harms is just beginning and will require constant evolution and vigilance to adapt to emerging threats.
    — Susan Morrisey, STAT, 15 Sep. 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 25 Sep. 2026.

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