The Pacific Ocean (from the Latin name Mare Pacificum, "peaceful sea", bestowed upon it by the Portuguese explorer Ferdinand Magellan) is the largest body of water on Earth.

The Pacific Ocean contains an estimated 20,000 to 30,000 islands; the exact number has not been precisely determined. Inhabitants are sometimes referred to as Pacific Islanders.

There are also many other islands located within the boundaries of the Pacific Ocean, but these are not considered part of Oceania.