In Wales, the Gwyllgi, pronounced /ˈɡwɪɬ,ɡi/, is a type of spectral Black Dog which occurs frequently in myths and ghost stories. Its name is a compound word of ci “dog,” and either gwyllt “wild,” or gwyll “twilight.” The word Gwyllgi is first cited as having appeared in a rare book, The Vale of Glamorgan (1839).
The Gwyllgi is usually described as a mastiff-like beast, about the size of a calf, with shaggy black fur; some accounts have other descriptions, such as the blood red Gwyllgi described in myths from the Afan and Margam district of South Wales. Another, near Llysworney in Glamorgan, was described as having spotted fur on the hind-quarters, but a man’s head instead of a dog’s. A Gwyllgi is typically said to have deadly breath and eyes which blaze red like hot coals.
Gwyllgŵn are said to haunt lonely lanes and isolated alleys at night or twilight. Many other places in the British Isles and the Iberian Peninsula have their own equivalent versions of the Black Dog, by many other titles. Examples of these are Mauthe Doog of the Isle of Man, Gytrash of Northern England, Barghest of Yorkshire, Dip of Catalona, Black Shuck of East Anglia, and the Church Grim, Padfoot, and Skriker of various parts of England.
Iron Noder 2013, 15/30