yellow jack

American  

noun

plural

yellow jack,

plural

yellow jacks

1. Informal. quarantine flag.

2. Pathology. yellow fever.

3. any carangoid fish, especially a Caribbean food fish, Caranx bartholomaei.

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yellow jack British  

noun

1. pathol another name for yellow fever

2. another name for quarantine flag

3. any of certain large yellowish carangid food fishes, esp Caranx bartholomaei, of warm and tropical Atlantic waters

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Etymology

Origin of yellow jack

An Americanism dating back to 1830–40

Example Sentences

But after performing an autopsy on the last man to die, he thought of yellow jack.

From Time Magazine Archive

When only the two soldiers who were bitten by mosquitoes contracted yellow jack, it amounted to Science's first important victory over yellow fever, the beginning of the final extermination of that plague.

From Time Magazine Archive

But all the time yellow jack was lurking in the jungles.

From Time Magazine Archive

Dr. Carroll caught yellow jack from one of the Finlay mosquitoes.

From Time Magazine Archive

He loathed the environment of that dim cell, with its slightly fœtid air, suggestive of yellow jack and dysentery.

From His Unknown Wife by Tracy, Louis