Tibia

n. pl. Tibiæ (#).
  1. (Anat.) The inner, or preaxial, and usually the larger, of the two bones of the leg or hind limb below the knee.
  2. (Zoöl.) The fourth joint of the leg of an insect. See Illust. under Coleoptera, and under Hexapoda.
  3. (Antiq.) A musical instrument of the flute kind, originally made of the leg bone of an animal.