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 This is a huge red flag for him, because a woman who loves her career won’t be a good mother to his future children. — Emma Sharpe, Vulture, 14 Oct. 2026 Raising the red flag are researchers at White Circle, a public benefit corporation backed by senior leaders and researchers from Anthropic, DeepMind, Hugging Face, and OpenAI. — Ashley Belanger, ArsTechnica, 14 Oct. 2026 Plus, Swifties saw Swift and Alwyn’s refusal to make joint public appearances as a red flag. — Lizzie Lanuza, StyleCaster, 7 Oct. 2026 DraftKings told Pearson that if a customer’s behavior raises too many red flags, the company will proactively close an account. — ProPublica, 6 Oct. 2026 See All Example Sentences for red flag
Recent Examples of Synonyms for red flag
  1. warning
  2. sign
Noun
  • Crash reported on northbound I-635 A traffic warning has been issued after a crash on I-635 from Shawnee Drive/Exit 1 to Metropolitan Avenue/Exit 2.
    — Kansas City Star Bot, Kansas City Star, 18 Oct. 2026
  • The warning is for Northern Jackson and Southern Jackson as well as Avery, Madison, Yancey, Mitchell, Swain, Haywood, Buncombe, Graham and Macon counties.
    — NC Weather Bot, Charlotte Observer, 18 Oct. 2026
Definition of warning
Noun
  • Vocals strain at the center of the songs while lonesome organs burn around the margins like the argon glow of a street-sign montage.
    — Gabriel Szatan, Pitchfork, 18 Oct. 2026
  • With hindsight, there were warning signs, said Constanze Stelzenmüller in the Financial Times.
    — The Week UK, TheWeek, 17 Oct. 2026
Definition of sign

Browse Nearby Words

red-eyes
red flag
red flags
See all Nearby Words

Cite this Entry

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

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