In Welsh mythology, a mother-goddess, the counterpart of the Irish Danu.
According to the Mabinogion , she was the sister of the magician-king Math and the mother of Gwydion (a master of magic and poetry) and Arianrhod, who was in turn the mother of Dylan (presumed to be a sea god) and Lleu Llaw Gyffes (probably the Welsh form of Lugus ).