Australia (ôstrāl'yu) [key], smallest continent, between the Indian and Pacific oceans. With the island state of Tasmania to the south, the continent makes up the Commonwealth of Australia, a federal parliamentary state (2005 est. pop. 20,090,000), 2,967,877 sq mi (7,686,810 sq km). Australia's capital is Canberra. Its largest city is Sydney, closely followed in population by Melbourne. There are five continental states (Queensland, New South Wales, Victoria, South Australia, and Western Australia, in addition to the aforementioned Tasmania) as well as the Northern Territory and the Australian Capital Territory (an enclave within New South Wales, containing Canberra). Australia's external territories include Norfolk Island, Christmas Island, the Cocos (Keeling) Islands, and the Australian Antarctic Territory.
