Papua New GuineaPap‧u‧a New Guin‧ea /ˌpæpuə njuː ˈɡɪni $ ˌpæpjuə nuː-/a country in the southwest Pacific Ocean, north of Australia, which includes the eastern half of the island of New Guinea and various small islands. Population: 6,431,902 (2014). Capital: Port Moresby.—Papuan noun, adjective