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.

---

black flag British  

noun

1. another name for the Jolly Roger

---

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

But the black flag isn’t a call for war, and neither the flag’s text nor the shrine’s statement about the banner references the coming of the Mahdi or the end of time.

From Seattle Times • Oct. 27, 2023

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

From Washington Times • May 23, 2023

A black flag will be flown on police buildings and service vehicles will display a mourning ribbon to honour the officer, Hungary's police department said.

From BBC • Jan. 13, 2023

Desperate to escape him, I entered the next building I came across—the Krupp Pavilion, a fortresslike structure whose tower was adorned with decorative eagles and the red, white and black flag of the German Empire.

From "The City Beautiful" by Aden Polydoros