Wiktionary
black belts
n. (plural of black belt English)
Usage examples of "black belts".
He was in uniform-of-the-day, but he was big, in training, and carried himself in a way that made me think of Black Belts.
Forrest saw Sharpe staring ruefully at the marching Riflemen with their green jackets and black belts.
We're both black belts in marital argument, so it's nothing to worry about.
A cluster of black belts larded with metal studs of different shapes and sizes hung from a wire hanger.
Bob Star watched the monstrous throng come down, until he could see the pattern of the tread on the black belts of the spheres, see the multiple heads of the silent giants.