red flag

noun

Definition of red flagnext
as in red light
something that tells of approaching danger or risk the résumé she accidentally left on the office printer was a red flag that she was planning to quit

Synonyms & Similar Words

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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 flag Meanwhile, the National Weather Service issued a red flag warning for the Central Coast and Santa Cruz Mountains beginning Friday morning amid concerns about potential lightning and strong winds. — Tim Fang, CBS News, 27 Aug. 2026 The state’s red flag firearms law may allow law enforcement to petition for a Risk Protection Order to temporarily remove firearms from those who pose a significant danger to themselves or others. — Evonne Andris, Miami Herald, 27 Aug. 2026 Villa rushed for 270 yards and four touchdowns, but giving up over 300 yards against Valencia raises red flags. — Ethan Hanson, Daily News, 27 Aug. 2026 Personally, my biggest beauty red flag is probably people who sleep in their makeup. — Lauren Valenti, InStyle, 26 Aug. 2026 See All Example Sentences for red flag
Recent Examples of Synonyms for red flag
  1. warning
  2. sign
Noun
  • Residents and visitors have been urged to closely monitor the weather and the watches or warnings as Lowell approaches the islands, the hurricane center said.
    — Dinah Voyles Pulver, USA Today, 8 Sep. 2026
  • The officer lets her off with a warning, and then everyone goes to bed.
    — Rafaela Bassili, Vulture, 8 Sep. 2026
Definition of warning
Noun
  • The enhanced scrutiny on Underwood, as Joe Rexrode writes, is an unfortunate sign of the times.
    — Chris Branch, New York Times, 8 Sep. 2026
  • The Bruins face a long and challenging season, but the Chesney Train won Game 1 and shows no signs of slowing down.
    — Connor Dullinger, Los Angeles Times, 7 Sep. 2026
Definition of sign

Browse Nearby Words

red-eyes
red flag
red flags
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Cite this Entry

“Red flag.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/red%20flag. Accessed 12 Sep. 2026.

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