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definitions

quarantine flag

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noun Nautical.

a yellow flag, designating the letter Q in the International Code of Signals: flown by itself to signify that a ship has no disease on board and requests a pratique, or flown with another flag to signify that there is disease on board ship.

Origin of quarantine flag

First recorded in 1870–75
Also called yellow flag.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for quarantine flag

Historical Examples of quarantine flag

  • Sick-room and sick-bed are also in common use, and sick-flag is used in place of the American quarantine-flag.

    The American Language

    Henry L. Mencken

  • In that of the midshipmen he may probably find a youth with the quarantine-flag up; that is, in the sick-list.

British Dictionary definitions for quarantine flag

quarantine flag

noun

nautical the yellow signal flag for the letter Q, flown alone from a vessel to indicate that there is no disease aboard and to request pratique or, with a second signal flag, to indicate that there is disease aboardAlso called: yellow flag, yellow jack
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