Source : Webster's Revised Unabridged Dictionary (1913)

Lamia \La"mi*a\, n. [L., fr. Gr. ?.] (Class. Myth.)
   A monster capable of assuming a woman's form, who was said to
   devour human beings or suck their blood; a vampire; a
   sorceress; a witch.

Source : WordNet®

lamia
     n : (folklore) a corpse that rises at night to drink the blood
         of the living [syn: {vampire}]
     [also: {lamiae} (pl)]