A title Geoffrey of Monmouth applies to Uther, the father of Arthur. Merlin sees a star in the heavens with a single ray ending in a fireball shaped like a dragon, and he associates the star and the dragon with Uther. When he becomes king, Uther has two golden dragons made, one for the cathedral of Winchester, the other to take into battle.
The name means Dragon's head, or rather "head dragon," as in "foremost leader."
- Lacy, Norris J., ed. (1996). The New Arthurian Encyclopedia. New York: Garland.