Pronunciation: (ul'stur),[key] —n. 1. a former province in Ireland, now comprising Northern Ireland and a part of the Republic of Ireland.
2. a province in N Republic of Ireland. 229,720; 3123 sq. mi. (8090 sq. km).
3. Informal.See Northern Ireland. 4. (l.c.) a long, loose, heavy overcoat, originally of Irish frieze, now also of any of various other woolen cloths.