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.
His red flag in a relationship is "someone who isn't careful with money" because he has always been "relatively prudent".
From BBC • Jul. 8, 2026
Areas of San Bernardino, Kern, Inyo and Tulare counties are under a red flag warning until 11 p.m.
From Los Angeles Times • Jun. 26, 2026
Despite its steep losses, the stock remains expensive—another red flag.
From Barron's • Jun. 24, 2026
Celebrities giving financial advice is a red flag for John Nowicki.
From The Wall Street Journal • Jun. 15, 2026
With the red flag planted in the earth beside him.
From "The God of Small Things" by Arundhati Roy
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.
