yellow jack

noun

, plural (especially collectively) yel·low jack, (especially referring to two or more kinds or species) yel·low jacks

1. Informal. quarantine flag.
2. Pathology. yellow fever.
3. any carangoid fish, especially a Caribbean food fish, Caranx bartholomaei.

yellow jack

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

Word History and Origins

Origin of yellow jack¹

An Americanism dating back to 1830–40

Example Sentences

Americans were well acquainted with yellow fever — or yellow jack as it was called.

From Washington Post

Then the dreaded "yellow jack" made its appearance amongst us, and forty men lay sick to death on the ballast, of whom, I grieve to relate, more than half died.

From Project Gutenberg

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

From Project Gutenberg

You eats a good dinner at twelve o’clock, and you are buried in the palisades at six; that’s called yellow jack.

From Project Gutenberg

We had not been there long, when yellow jack, as the yellow fever is called, made its appearance, both at Kingston and Port Royal, and all visits to the shore were prohibited.

From Project Gutenberg