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Synonyms

red flag

1 American  

noun

  1. the symbol or banner of a left-wing revolutionary party.

  2. a danger signal.

  3. something that provokes an angry or hostile reaction.

    The talk about raising taxes was a red flag to many voters.

  4. Also called powder flagNautical. 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.

  5. (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.


red-flag 2 American  
[red-flag] / ˈrɛdˈflæg /

verb (used with object)

red-flagged, red-flagging
  1. to mark or draw attention to for a particular purpose.

    The department has red-flagged the most urgent repair work to be done.

  2. to provoke the attention of; alert; arouse.

    The animal's refusal to eat red-flagged the keeper that something was wrong.


adjective

  1. of or relating to a red flag.

  2. intended or serving to emphasize, warn, incite, or provoke.

red flag 1 British  

noun

  1. a symbol of socialism, communism, or revolution

  2. a warning of danger or a signal to stop

"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

Red Flag 2 British  

noun

  1. 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

Etymology

Origin of red flag1

First recorded in 1770–80

Origin of red-flag2

First recorded in 1880–85

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.

“The biggest problem with somebody with Neff’s history is the giant screaming red flag that involves filing a prosecution based on unreliable evidence,” Levitt said.

From Los Angeles Times

The red flag with central yellow star stayed official in the home country, while the Southern yellow flag with three red stripes became a refugee reminder in the United States.

From Salon

If you are being pushed to do so, that is a red flag.

From MarketWatch

Isolation is a major sign of elder financial abuse, and preventing you from seeing your mother is a huge red flag.

From MarketWatch

However, “businesses owning 10% of total equities, similar to the Y2K’s top, would highlight a major ‘red flag,’” he says.

From MarketWatch