quarantine flag

American  

noun

Nautical.

1. 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.

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quarantine flag British  

noun

1. Also called: yellow flag.   yellow jack.  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 aboard

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Etymology

Origin of quarantine flag

First recorded in 1870–75

Example Sentences

It is advisable to fly a yellow quarantine flag as you enter the Bahamas until you�ve cleared customs.

From Time Magazine Archive

They would have nothing to do with us; so the yellow quarantine flag was hoisted, and we waited for permission to land the Cadiz party.

From Fragments of science, V. 1-2 by Tyndall, John

Why did he not at this time hoist his quarantine flag and warn every one that he was dangerous to come near?

From The Oxford Movement Twelve Years, 1833-1845 by Church, R. W. (Richard William)

"Miss Carstow," she prompted, in a voice that seemed to raise a quarantine flag above him.

From The Lighted Match by Schabelitz, R. F.

"We should blush to sail away from Mr. Wade, while he carries the quarantine flag at his pale cheeks."

From The Atlantic Monthly, Volume 09, No. 52, February, 1862 by Various