GLASH, or GLASS, an island, in the parish of KILBELFAD, barony of TYRAWLEY, county of MAYO, and province of CONNAUGHT, 6 miles (S. W.) from Ballina: the population is returned with the parish. This small island, which is situated in Lough Conn, about a mile from the mainland, comprises some good arable land, with a portion of rocky pasture. It is remarkable chiefly as the asylum of Bishop Baiefadda, who took refuge here during the times of early persecution; there are still the remains of a church, and the burial-place in which he was interred.