Synonyms of red flag

red flag

noun

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

• red light
• warning
• handwriting on the wall
• sign
• wake-up call
• tocsin
• tip-off
• signal
• indicator
• caution
• notification
• premonition
• omen
• buoy
• declaration
• portent
• presage
• announcement
• notice
• foretaste
• knell
• foretoken

Antonyms & Near Antonyms

• green light
• permission
• OK
• go-ahead
• all clear

Example Sentences

Recent Examples of red flag

The campaign’s long-game strategy is the red flag for the agricultural industry and for sportsmen. — Kris Millgate, Outdoor Life, 9 July 2026

The red flags waving so brightly today were fully visible a month ago. — David Frum, The Atlantic, 8 July 2026

The map also overlays the location of water hydrants, the moisture content of vegetation, wildfire history, red flag warnings of dangerous fire conditions and other data. — Bloomberg, Mercury News, 8 July 2026

Below, members of Forbes Coaches Council share the practices that help the most effective boards thrive, along with red flags that commonly characterize the most dysfunctional ones. — Expert Panel®, Forbes.com, 7 July 2026