The term "Seven Seas" historically referred to regional waters and bodies of water along trade routes. However, in some references the seas are mythical and not real water bodies. Presently, the Seven Seas refers to the seven oceans.
Different cultures and civilizations have had different understandings for term the "Seven Seas." The term is mentioned by the ancient Chinese, Hindus, Romans and Persians. The first reference of the term is from ancient Sumer in 2300 B.C. in a hymn. To the Persians, the term meant the streams of water forming the Oxus River, while the ancient Romans used the term to refer to a group of salt-water lagoons. The ancient Arabs and the Phoenicians used the term to define the waters along their trading routes.
The Romans and the Greeks gave the medieval definition of the term, while the Europeans had their own definition of the term during the New Age and the Colonial Era. The Europeans coined the term “Sailed the Seven Seas” to mean sailing to different parts of the world and back.
Geographers currently use the term the Seven Seas to refer to the seven oceans: the North and South Atlantic Oceans, the North and South Pacific Oceans, the Arctic Ocean, the Southern Ocean and the Indian Ocean.