Greatest of the wolves or "werewolves" of Morgoth/Sauron in Tolkien's book The Silmarillion. Fathered by Draugluin, Carcharoth was specially trained and fed up to be the most powerful
wolf ever, because of a prophecy that Huan the wolfhound could only be killed by the greatest
wolf in
history.
Carcharoth was posted outside the fortress of Angband to protect Sauron from any attempt by Beren, Luthien and Huan to obtain a Silmaril (in fulfilment of their oath to Elwe). Put under a sleep spell by Luthien, he failed to prevent the theft of a Silmaril, but he attacked Beren when he tried to leave the tower, biting off the
hand containing the Silmaril.
Tormented by its
light which he found unbearable, Carcharoth then ran rampage across Beleriand until hunted down and slain by Huan. As the prophecy foretold, Huan was also slain in this combat.