Red Flag

What is a red flag?

A warning sign

A red flag is a sign that indicates you should be wary or cautious of someone or something. It may be used to warn about concerning traits in people, houses, vehicles, plans, jobs, games, etc.

The term comes from the use of actual red-colored flags to warn people of danger, whether it be on a racetrack when a crash occurs or a beach with strong rip tides. Red flag is often used in regards to relationships when determining if potential partners are worth investing in or if they have too many "deficiencies."


He told me that he had 5 GFs in the last 2 years, which was a major red flag

Swift talking about the red flag double standard between men and women

Related Slang


Updated July 31, 2019

Red flag definition by

This page explains what the slang term "Red flag" means. The definition, example, and related terms listed above have been written and compiled by the team.

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