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code flag

American  

noun

Nautical.

  1. a flag forming part of a signal code.

  2. a flag indicating that a certain signal code is being used.

  3. answering pennant.

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.