Dictionary.com
Thesaurus.com

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

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.

Vocabulary.com logo
by dictionary.com

Look it up. Learn it forever.

Remember "yellow flag" for good with VocabTrainer. Expand your vocabulary effortlessly with personalized learning tools that adapt to your goals.

Take me to Vocabulary.com