Borders of the oceans seas it contains) as follows: Note that these definitions exclude any marginal waterbodies that are separately defined by the IHO (such as the Kara Sea and East Siberian Sea), though these are usually considered to be part of the Arctic Ocean. The CIA defines the limits of the Arctic Ocean differently, as depicted in the map comparing its definition to the IHO's definition. The Atlantic Ocean separates the Americas from Europe and Africa. It may be further subdivided by the equator into northern and southern portions. The 3rd edition, currently in force, of the International Hydrographic Organization's (IHO) "Limits of
Seven Seas Seven Seas The "Seven Seas" (as in the idiom "sail the Seven Seas") is an ancient phrase for all of the world's oceans. Since the 19th century, the term has been taken to include seven oceanic bodies of water: The World Ocean is also collectively known as just "the sea". The International Hydrographic Organization lists over 70 distinct bodies of water called seas. The term "Seven Seas" appears as early as 2300 BC in Hymn 8 of the Sumerian Enheduanna to the goddess Inanna. The Mesopotamians were the first in the history of astronomy to keep records of the observed