Chokebore

Part of speech: noun (n.)

1. In a shotgun, a bore which is tapered to a slightly smaller diameter at a short distance (usually 2½ to 3 inches) to the rear of the muzzle, in order to prevent the rapid dispersion of the shot.

2. A shotgun that is made with such a bore.

Part of speech: verb (v.)

To provide with a chokebore.