Muzzle/ˈmʌzl/ Definition 1 of 5Pro Tip 1/2Animal Feature Refers to the protruding part of certain animals' faces. A horse's muzzle is often velvety to the touch. Pro Tip 2/2Beyond Dogs While common in dogs, 'muzzle' applies to other animals too. The goat's white muzzle stood out against its dark fur.