Cushlannaig (plural, or plurale tantum?; singular unknown)
plural: = singular?; (with) definite article: ?According to Conran "mentioned in the Irish poems and other writings of various dates, from the 10th to the 16th century".
Conran, Michael: The national music of Ireland, containing the history of the Irish bards, the national melodies, the harp, and other musical instruments of Erin [1846]. London & Manchester, 1850 (2), p.120.