Glaurung is the dragon slain by Túrin in J.R.R. Tolkien’s legendarium.
Glaurung is a major antagonist in the First Age story later known as The Children of Húrin. He is described as the first of the great dragons bred by Morgoth, the primary dark power of Tolkien’s early mythology.
The dragon possesses intelligence, speech, and a hypnotic power over those who meet his gaze. His actions help bring about the tragic fate of Túrin and Túrin’s sister Nienor. Túrin eventually kills Glaurung with his sword Gurthang at Cabed-en-Aras.
Glaurung is not Smaug, the dragon of The Hobbit. Ancalagon the Black is another First Age dragon, famous for his role in the War of Wrath, while Scatha belongs to a later history of Middle-earth. These dragons are separate characters.