Australia is the only country that is also a continent. In area, Australia ranks as the sixth largest country and smallest continent. Australia is located between the South Pacific Ocean and the Indian Ocean. The part of the Indian Ocean that is south of Australia is called the Southern Ocean in the country. Australia is about 7,000 miles (11,000 kilometers) southwest of North America and about 2,000 miles (3,200 kilometers) southeast of mainland Asia. Australia is often referred to as being "down under" because it lies entirely within the Southern Hemisphere. The name Australia comes from the Latin word australis, which means southern. The official name of the country is the Commonwealth of Australia.