- a large island N of Australia, politically divided into the Indonesian province of Irian Jaya (West Irian) and the independent country of Papua New Guinea. About 316,000 sq. mi. (818,000 sq. km).
- an island in the W Pacific, north of Australia: divided politically into Papua (formerly Irian Jaya, a province of Indonesia) in the west and Papua New Guinea in the east. There is a central chain of mountains and a lowland area of swamps in the south and along the Sepik River in the north. Area: 775 213 sq km (299 310 sq miles)
- (until 1975) an administrative division of the former Territory of Papua and New Guinea, consisting of the NE part of the island of New Guinea together with the Bismarck Archipelago; now part of Papua New Guinea