Adelaide is the capital and most populous city of South Australia, as well as the fifth and sixth most populous cities in Australia and Oceania, r…Adelaide is the capital and most populous city of South Australia, as well as the fifth and sixth most populous cities in Australia and Oceania, respectively. The name "Adelaide" may refer to either Greater Adelaide or the Adelaide city centre. The demonym Adelaidean is used to denote the city and the residents of Adelaide. The traditional owners of the Adelaide region are the Kaurna. The name Tarndanya in their language refers to the area of the city centre and surrounding Park Lands.