Cunedda. [W] Cunedda and his eight sons settled in Wales and founded the Welsh kingdoms. His story is similar to the story of Mil and his eight sons, who went to Ireland and founded the kingdoms there. Tybion, Cunedda's eldest son, for example, like Donn, eldest son of Mil, dies before the family settles in Wales, although his son Meirion takes his father's place (as Lugaid, son of Ith, does in Irish myth). Cunedda is the eponymous founder of the dynasty of Gwynedd, while his sons form other kingdoms such as Ceredigion (Cardigan).

Curad-mir. [I] "The Hero's Portion," a motif that features in such tales as "Mac Da Tho's Boar" and "Bricriu's Feast." It is a choice cut of meat, usually a piece of thigh, reserved for the greatest champion attending a feast, and therefore this apportionment was often the start of a quarrel between the warriors.

Cu RoI. [I] Son of Daire and a king of Munster. In one of the prototype versions of the theme that became famous in the story "Sir Gawain and the Green Knight," it is Cu Roi who presents himself to the Red Branch warriors and challenges them to cut off his head and then to let him retaliate. In most of the stories in which he appears there is nothing supernatural about him and he is finally slain by Cuchulainn after he kidnaps Blathnat, daughter of the king of Inis Fer Falga. .

Curragh. [I] Cognate with the Welsh cwrwgl (coracle). The most popular of boats used in the sagas and tales.

Custennin. [W] A giant shepherd in the territory of Yspaddaden the Giant who, with his wife, helps Culhwch in his quest for Olwen. They arrange for Olwen to meet Culhwch at their house. There is a further symbolism here, for Custennin's wife is actually Culhwch's aunt (his mother's sister), and in their house two worlds meet-the real world and the world of giants. In some versions he is made the brother of Yspaddaden.

Cwn Annwn. [W] The hounds of the Otherworld, perhaps translated as "hounds of hell." They first appear as the hounds of Arawn in the story where Pwyll chases then off a deer so that he might claim it.Then Gwyn ap Nudd has domain over them. Folklore in Wales has created many evil creatures with white bodies and red ears, racing through the countryside on dark, stormy nights, pursuing the souls of unshriven men or unbaptised children. The folk tradition of the "hounds of hell " emanating from Celtic myth is fairly widespread even in non-Celtic areas.

Cwrwgl. [W] See Curragh.

Cwy. [W] A mysterious person referred to by Taliesin: I will not allow much praise to the spiritless. They know not on what day, or who caused it, Or in what hour of the serene day Cwy was born, Or who caused that he should not go to the dales of Defwy, They know not the brindled ox with the broad headband, Whose yoke is seven-score handbreadths. When we went with Arthur of mournful memory, Except seven, none returned from Caer Fandwy. No one has satisfactorily discovered the meaning of this verse.

Cyfarwydd. [W] A professional storyteller like the seanchaidhe (or seanchai) of Ireland.

Cyfwlch. [W] One of three warriors who possess the brightest and sharpest weapons at Arthur's fortress. The others are Bwlch and Syfwlch.

Cymidei Cymeinfoll.- [W] "The big-bellied battler." The wife of Llasar Llaesgyfnewid. She and her husband appear to be deities of war for they own a magic cauldron. If a slain warrior were cast into it he would come forth alive again except that he would have no power of speech. When they were in Ireland, Cymidei would give birth to a fully armed warrior every six weeks. Matholwch of Ireland tried to destroy them but they escaped to Britain where Bran gave them refuge. In return they gave him the cauldron. When Efnisien insulted Matholwch on the eve of his wedding to Branwen, Bran gave him the cauldron as a means of atonement.

Cymon. [W] A warrior at Arthur's court. He appears in a Welsh version of "Le Chevalier au lion" of Chretien de Troyes. He comes across a black man with one foot and one eye, bearing a mighty club, in a glade in a forest with wild animals, stags, and serpents feeding by him. Cymon was looking for a combat and the man told him to go to a fountain, take a silver bowl he would find there, and fill it with water. The water must then be thrown on a nearby marble slab. A thunderstorm would follow, and the singing of enchanted birds, and a Black Knight would appear. Though couched in medieval guise, many things about the tale are of eatlier Celtic origin. The Black Knight defeats Cymon, who returns to Arthur's court where Owain ap Urien is fired by his tale and sets out to defeat the Black Knight. The rest of the story belongs to Owain, except for when, after he had been missing from the court for three years, Arthur and Gwalchmai and a band of warriors, with Cymon as their guide, set forth to find him. They eventually find him well and prospering in the Castle of the Fountain.

Cymric. Pertaining to Wales or sometimes more widely to British Celtic. The ancestor language and culture of Welsh, Breton, and Cornish.

Cymru. The land of comrades or of fellow-countrymen. It derives from the British combrogos, "compatriot." See Cumbria and Wales.

Cynddelig. [W] A member of Arthur's retinue who guides Culhwch in his quest for Olwen.

Cynddylan. [W] Son of Cyndrwyn, lord of Pengwern. He is mentioned in a seventh century elegy but also features in the later sagaliterature.

Cynghanedd. A metrical system of multiple alliteration and rhyme within every line of the Welsh strict poetic metre.

Cythrawl. [W] Identified as two primary existences, destruction and life.

Cywydd. A form of strict metre in Welsh poetry and a dominant form until the eighteenth century. .