Sea

The term sea refers to certain large bodies of water, but there is inconsistency as to its precise definition and application. Most commonly, a sea may refer to a large expanse of saline water connected with an ocean, but it is also used sometimes of a large saline lake that lacks a natural outlet, e.g. the Caspian Sea. Colloquially, the term is used as a synonym for ocean. Additionally, large lakes, such as the Great Lakes, are occasionally referred to as inland seas.

International Hydrographic Organization

The International Hydrographic Organization (IHO) is the international authority that sets forth nomenclature and definition of bodies of water.^[1] The IHO's Limits of Oceans and Seas was first published in 1928, with its current working document the third edition published in 1953.^[2] A fourth draft edition was proposed in 1986 but has yet to be ratified due to outstanding issues such as the Sea of Japan naming dispute.

The term "sea" has also been used in quantum physics. Dirac sea is an interpretation of the negative energy states that comprises the vacuum.

http://en.wikipedia.org/wiki/Sea

IHO, IHO, its off to work we go~!