The horny sheath covering the toes or lower part of the foot of a mammal of the orders Perissodactyla and Artiodactyla,such as a horse,an ox,or a deer.

• 蹄覆盖奇蹄目或偶蹄目哺乳动物脚趾或足下部的角质鞘，如马，牛或鹿