Source : Webster's Revised Unabridged Dictionary (1913)

Tibia \Tib"i*a\, n.; pl. {Tibi[ae]}. [L.]
   1. (Anat.) The inner, or preaxial, and usually the larger, of
      the two bones of the leg or hind limb below the knee.

   2. (Zo["o]l.) 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      originally made of the leg bone of an animal.

Source : WordNet®

tibia
     n : the inner and thicker of the two bones of the human leg
         between the knee and ankle [syn: {shinbone}, {shin}]
     [also: {tibiae} (pl)]

tibiae
     See {tibia}