muzzle

the open circular discharging end of a gun

forward projecting part of the head of certain animals; includes the jaws and nose

a leather or wire restraint that fits over an animal's snout (especially a dog's nose and jaws) and prevents it from eating or biting

restraint put into a person's mouth to prevent speaking or shouting

fit with a muzzle; "muzzle the dog to prevent it from biting strangers"

prevent from speaking out; "The press was gagged"

tie a gag around someone's mouth in order to silence them; "The burglars gagged the home owner and tied him to a chair"