What is the meaning of muzzle?

noun

• The open circular discharging end of a gun.
  • synonyms: gun muzzle
• 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.
  • synonyms: gag

verb

• Fit with a muzzle.
  • usage: "muzzle the dog to prevent it from biting strangers"
• Prevent from speaking out.
  • usage: "The press was gagged"
  • synonyms: gag
• Tie a gag around someone's mouth in order to silence them.
  • usage: "The burglars gagged the home owner and tied him to a chair"
  • synonyms: gag