[cf. W còr, corrach, dwarf].
A magical and demonic people who invade and harass Britain in Cyfranc Lludd a Llefelys [The Story of Lludd and Lleuelys]. They have been identified in a general way with fairies, but are far more malevolent than the tylwyth teg of Welsh oral tradition. One of three invaders that threatened the kingdom of Lludd, they could hear sound carried on the wind.