The Collaborative International Dictionary of English v.0.48:

Werewolf \Were"wolf`\, n.; pl. Werewolves. [AS. werwulf; wer a
   man + wulf a wolf; cf. G. w[aum]rwolf, w[aum]hrwolf,
   wehrwolf, a werewolf, MHG. werwolf. [root]285. See Were a
   man, and Wolf, and cf. Virile, World.]
   A person transformed into a wolf in form and appetite, either
   temporarily or permanently, whether by supernatural
   influences, by witchcraft, or voluntarily; a lycanthrope.
   Belief in werewolves, formerly general, is not now extinct.
   [1913 Webster]

         The werwolf went about his prey.         --William of
                                                  Palerne.
   [1913 Webster]

         The brutes that wear our form and face,
         The werewolves of the human race.        --Longfellow.
   [1913 Webster] Werk