Hound of Sauron

Gandalf's name for one of the dark wolves, or creatures in wolf-shape, that attacked the Fellowship of the Ring in the empty lands westward of the Mountains of Moria. There were in fact many of these Hounds of Sauron, though only one was directly addressed in this way (and was despatched soon afterwards by an arrow from Legolas).

These creatures were only 'hounds' in the most general sense, as they were clearly identified as wolves, but wolves of a peculiarly spectral kind, leaving no bodies after being slain. A clue to their nature comes from a spell in Sindarin that Gandalf cast at this time, which named the beasts as ngaurhoth, 'werewolves'. This Elvish word connects the Hounds of Sauron back to the First Age, when Sauron ruled Tol-in-Gaurhoth, the Isle of Werewolves. It was known that the Dark Lord had werewolves among his forces during the War of the Ring, too, though the attacking Hounds of Sauron were the only such creatures actually encountered during the War.