1. The world's smallest continent, southeast of Asia between the Pacific and Indian Oceans.
2. A commonwealth comprising the continent of Australia, the island state of Tasmania, and several island territories and dependencies. The continent was inhabited by Aboriginal peoples for at least 40,000 years before the first British settlement, a penal colony at Port Jackson (now part of Sydney), was established in 1788. The present-day states grew as separate colonies; six of them formed a federation in 1901. In 1911 Northern Territory joined the commonwealth and the Capital Territory, site of Canberra, was created. Canberra is the capital and Sydney is the largest city.