the symbol or banner of a left-wing revolutionary party.
a danger signal.
something that provokes an angry or hostile reaction.
The talk about raising taxes was a red flag to many voters.
Also called powder flag. Nautical. a red burgee, designating in the International Code of Signals the letter “B,” flown by itself to show that a vessel is carrying, loading, or discharging explosives or highly inflammable material.
(initial capital letters) a war game the U.S. Air Force holds several times each year at Nellis Air Force Base, Nevada, to train personnel in air combat.
to mark or draw attention to for a particular purpose.
The department has red-flagged the most urgent repair work to be done.
to provoke the attention of; alert; arouse.
The animal's refusal to eat red-flagged the keeper that something was wrong.
of or relating to a red flag.
intended or serving to emphasize, warn, incite, or provoke.
a symbol of socialism, communism, or revolution
a warning of danger or a signal to stop
First recorded in 1770–80
First recorded in 1880–85
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
He’s waving a red flag about the very real chance that SpaceX, Anthropic, and OpenAI will create an “impending chokepoint.”
From Barron's • Jun. 9, 2026
Helped by the red flag chaos to score big points but always looked like he was on for a top-10 finish.
From BBC • Jun. 7, 2026
This was either a red flag or a very Los Angeles credential, depending on the neighborhood.
From Los Angeles Times • Jun. 5, 2026
But the sheer size of SpaceX’s expected offering, and Chief Executive Elon Musk’s expressed desire to have significant retail ownership, might make that less of a red flag this time around.
From The Wall Street Journal • Jun. 4, 2026
A red flag waved for me, something chemical happened inside me, every time I heard that.
From "The Autobiography of Malcolm X" by Alex Malcolm X;Hailey
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
