Today the term South Seas, or South Sea, most commonly refers to the portion of the Pacific Ocean south of the equator.[1][2][3] The term South Sea may also be used synonymously for Oceania, or even more narrowly for Polynesia or the Polynesian Triangle, an area bounded by the Hawaiian Islands, New Zealand and Easter Island. Pacific Islanders are commonly referred to as South Sea Islanders, particularly in Australia.
The term was first coined as Mar de Sur, or “South Sea,” by Spanish conquistador Vasco Núñez de Balboa in 1513 and was applied to the entire area of today's Pacific Ocean. In 1520, Ferdinand Magellan named the same ocean the Pacific Ocean, and over time Magellan's name became more well-known.