red flag


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.



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Origin of red flag

First recorded in 1770–80

Definition for red flag (2 of 2)

[ red-flag ]
/ ˈrɛdˈflæg /

verb (used with object), red-flagged, red-flag·ging.

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.

Origin of red-flag

First recorded in 1880–85 Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020

Example sentences from the Web for red flag

  • When it gets parched in Los Angeles the weather service issues a “red-flag” warning to indicate that the risk of fire is high.

    NBC Universal Sees Red|Kim Masters|July 19, 2009|DAILY BEAST
  • A lot of them fur-faced boys that hurl the merry bombs are goin' to pull off a red-flag sashay up the Avenoo.

    The Wrong Twin|Harry Leon Wilson

British Dictionary definitions for red flag (1 of 2)

red flag


a symbol of socialism, communism, or revolution
a warning of danger or a signal to stop

British Dictionary definitions for red flag (2 of 2)

Red Flag


the Red Flag a socialist song, written by James Connell (1852–1929), Irish political activist, in 1889
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012