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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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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 flag Detective Barry told Chamberlain this raised many red flags for the investigative team. — Jeremy Greenberg, ABC News, 14 Sep. 2026 However, one four-play stretch in the second half should raise some red flags. — Nick Harris, Fort Worth Star-Telegram, 14 Sep. 2026 These are proactive, temporary electricity shutoffs to prevent high-voltage power lines and equipment from sparking wildfires during red flag weather conditions. — Clara Harter, Los Angeles Times, 11 Sep. 2026 But the fact that George left Reeger’s side after the battle at Zeta Reticuli has raised some red flags for him. — Keith Phipps, Vulture, 10 Sep. 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 20 Sep. 2026.

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