muzzle

A Border Collie wearing a yellow greyhound muzzle. A muzzle is a device that is placed over the snout of an animal to keep them from biting or otherwise opening their mouth.

Muzzles can be primarily solid, with air holes to allow the animal to breathe, or formed from a set of straps that provides better air circulation and allow the animal to drink, and in some cases, eat. Leather, wire, plastic, and nylon are common materials for muzzles. The shape and construction of the muzzle might differ depending on whether the intent is to prevent an animal from biting or from eating, for example.