(На самом деле - "late O.E. werewulf "person with the power to turn into a wolf," from wer "man" + wulf (see wolf; also see here for a short discussion of the mythology). The first element probably is from PIE *uiHro "freeman" (cf. Skt. vira-, Lith. vyras, L. vir, O.Ir. fer, Goth. wair). Cf. M.Du. weerwolf, O.H.G. werwolf, Swed. varulf. In the ancient Persian calendar, the eighth month (October-November) was Varkazana-, lit. "(Month of the) Wolf-Men."" - http://www.etymonline.com/index.php?term=werewolf . Или: "An alternative etymology derives the first part from Old English weri (to wear); the full form in this case would be glossed as wearer of wolf skin. Related to this interpretation is Old Norse ulfhednar, which denoted lupine equivalents of the berserker, said to wear a bearskin in battle.
Yet other sources derive the word from warg-wolf, where warg (or later werg and wero) is cognate with Old Norse vargr, meaning "rogue," "outlaw," or, euphemistically, "wolf". A Vargulf was the kind of wolf that slaughtered many members of a flock or herd but ate little of the kill. This was a serious problem for herders, who had to somehow destroy the rogue wolf before it destroyed the entire flock or herd. The term Warg was used in Old English for this kind of wolf. Possibly related is the fact that, in Norse society, an outlaw (who could be murdered with no legal repercussions and was forbidden to receive aid) was typically called vargr, or "wolf."" - http://en.wikipedia.org/wiki/Werewolf ).
Забавно: "Surnames like Lowell, Lovel, and Lovett are versions of diminutives of "wolf" in Old French or Anglo-Norman, either from nicknames "wolf cub," or meaning "son of Wolf." (http://www.etymonline.com/wolf.php )