Lismore (lĬsmôr´, lĬz–), town (1991 pop. 715), Co. Waterford, S Republic of Ireland, on the Blackwater River. It is a market town with a salmon fishing industry. In the 7th cent., St. Carthagh founded a monastery there. By the 8th cent. it was a famed center of learning. Lismore Castle, which has been restored, was built under Prince (later King) John in 1185. Robert Boyle was born in Lismore.

Lismore (lĬz´môr, lĬzmôr´), island, 91/2 mi (15.3 km) long and 11/2 mi (2.4 km) wide, Argyll and Bute, W Scotland, in Loch Linnhe. There are ruins of several old castles, one of which was a 9th-century Viking fortress, another the residence of the bishops of Argyll. The present parish church was the choir of a 13th-century cathedral. The 16th-century Book of the Dean of Lismore is a volume of Scottish Gaelic and other verse, compiled by Dean James Macgregor and his brother Duncan. It is one of the oldest Scottish Gaelic collections.

Lismore (lĬz´môr), city (1991 pop. 27,246), New South Wales, E Australia, on the North Arm of the Richmond River. An important industrial city, Lismore is a leading producer of butter. Its port is Ballina.