Source : Webster's Revised Unabridged Dictionary (1913)

Hallux \Hal"lux\, n. [NL., fr. L. hallex, allex.] (Anat.)
   The first, or preaxial, digit of the hind limb, corresponding
   to the pollux in the fore limb; the great toe; the hind toe
   of birds.

Source : WordNet®

hallux
     n : the first largest innermost toe [syn: {big toe}, {great toe}]
     [also: {halluces} (pl)]