red flag

NOUN

warning signal

Synonyms

WEAK

casus belli delicate subject red light red rag sore point

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

So this retreat is a bit of a red flag.

From Barron's • May 4, 2026

Ratios in the double-digits are a classic red flag.

From The Wall Street Journal • Apr. 21, 2026

That is always a red flag for me when I’m reading an OLC opinion.

From Slate • Apr. 9, 2026

"He never had a single red flag at all."

From BBC • Apr. 7, 2026

A man was waving them on with a red flag tied to a stick.

From "The Kill Order (Maze Runner, Book Four; Origin)" by James Dashner