black flag

American  

noun

1. a pirate flag, usually of black cloth with a white skull and crossbones on it; Jolly Roger.

2. a flag having two yellow and two black squares, signifying the letter L in the International Code of Signals: formerly so called when used by itself to indicate the presence of cholera on board a vessel.

3. a signal given to an automobile racing driver to stop, usually because the car may have a dangerous problem that requires inspection.

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black flag British  

noun

1. another name for the Jolly Roger

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Etymology

Origin of black flag

First recorded in 1585–95

Example Sentences

At the Islam Qala border crossing on Sunday, an AFP journalist said it remained open and a black flag had replaced the Iranian standard.

From Barron's • Mar. 1, 2026

The green and black flag of the opposition, now ubiquitous, stands out.

From BBC • Dec. 17, 2024

Chapman scrambled to the officials’ stand, pleading with Chief Steward Harlan Fengler to put out a black flag for Jones, calling him to the pits.

From Los Angeles Times • Jun. 5, 2024

The red, white and black flag was placed on the sidewalk and can be seen in footage posted by Fox 5.

From Washington Times • May 23, 2023

From here, callers announced new voyages and arrivals of inventory, or hung the black flag that indicated that a ship had been lost at sea with all its cargo.

From "Six of Crows" by Leigh Bardugo