Source : Webster's Revised Unabridged Dictionary (1913)

Harpy \Har"py\, n.; pl. {Harpies}. [F. harpie, L. harpyia, Gr.
   ?, from the root of ? to snatch, to seize. Gf. {Rapacious}.]
   1. (Gr. Myth.) A fabulous winged monster, ravenous and
      filthy, having the face of a woman and the body of a
      vulture, with long claws, and the face pale with hunger.
      Some writers mention two, others three.

            Both table and provisions vanished guite. With sound
            of harpies' wings and talons heard.   --Milton.

   2. One who is rapacious or ravenous; an extortioner.

            The harpies about all pocket the pool. --Goldsmith.

   3. (Zo["o]l.)
      (a) The European moor buzzard or marsh harrier ({Circus
          [ae]ruginosus}).
      (b) A large and powerful, double-crested, short-winged
          American eagle ({Thrasa["e]tus harpyia}). It ranges
          from Texas to Brazil.

   {Harpy bat} (Zo["o]l.)
      (a) An East Indian fruit bat of the genus {Harpyia} (esp.
          {H. cerphalotes}), having prominent, tubular nostrils.
      (b) A small, insectivorous Indian bat ({Harpiocephalus
          harpia}).

   {Harpy fly} (Zo["o]l.), the house fly.

Source : WordNet®

harpy
     n 1: a malicious fierce-tempered woman [syn: {vixen}, {hellcat}]
     2: (Greek mythology) vicious winged monster; often depicted as
        a bird with the head of a woman
     3: any of various fruit bats of the genus Nyctimene
        distinguished by nostrils drawn out into diverging tubes
        [syn: {harpy bat}, {tube-nosed bat}, {tube-nosed fruit bat}]
     4: large black-and-white crested eagle of tropical America
        [syn: {harpy eagle}, {Harpia harpyja}]