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yellow flag

American  

noun

  1. Nautical. quarantine flag.

  2. water flag.

yellow flag British  

noun

  1. another name for quarantine flag

  2. See flag 3

"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 yellow flag

First recorded in 1775–85

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 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 • Dec. 31, 2025

But if that should fall to the S&P 500 median of 10 times, it “would raise a yellow flag that debt payments are becoming burdensome,” says Emanuel.

From MarketWatch • Dec. 29, 2025

The 24-lap dash finished under a yellow flag after Gabriel Bortoleto's Sauber suffered a big crash.

From Barron's • Nov. 8, 2025

They had given a particularly warm welcome to the Ukrainian contingent in the parade, carrying the blue and yellow flag of their country.

From BBC • May 5, 2025

Last Respects After two weeks at sea the commander calls all of us above deck for a formal lowering of our yellow flag with three red stripes.

From "Inside Out and Back Again" by Thanhha Lai

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.