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

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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 Like people in other communities, attendees raised red flags about the climate concerns. — Laura Horne, Charlotte Observer, 13 Aug. 2026 Investigative Journalist Jon Marcus from The Hechinger Report breaks down why fewer than half of affected students ever finish their degrees and what red flags families should watch for. — Dana Taylor, USA Today, 13 Aug. 2026 The red flag warning is an update of an earlier fire weather watch alert by the agency, Sacramento Bee meteorologist Sean Macaday reported. — Don Sweeney, Sacbee.com, 12 Aug. 2026 Hair on the floor, residue in the shower, or anything left behind by a previous guest is an immediate red flag. — Lauren Dana Ellman, Travel + Leisure, 12 Aug. 2026 See All Example Sentences for red flag
Recent Examples of Synonyms for red flag
  1. warning
  2. sign
Noun
  • Some news stations would run a warning for viewers before the ad would air, as well as explain the FCC law requiring its airing.
    — Jeff Wagner, CBS News, 11 Aug. 2026
  • Amazon's Accounting Sets A Shorter Clock Amazon's books offer a warning.
    — Robert J. Szczerba, Forbes.com, 11 Aug. 2026
Definition of warning
Noun
  • There are signs that domestic hardware is beginning to take a larger role.
    — Neetika Walter, Interesting Engineering, 11 Aug. 2026
  • The remnants of the Boston Market restaurant sign are still visible … but not for long.
    — Linda Zavoral, Mercury News, 11 Aug. 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 16 Aug. 2026.

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More from Merriam-Webster on red flag

Nglish: Translation of red flag for Spanish Speakers

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