Atlantic Ocean as the mid-19th century. During the Age of Discovery, the Atlantic was also known to English cartographers as the Great Western Ocean. The International Hydrographic Organization (IHO) defined the limits of the oceans and seas in 1953, but some of these definitions have been revised since then and some are not used by various authorities, institutions, and countries, see for example the CIA World Factbook. Correspondingly, the extent and number of oceans and seas varies. The Atlantic Ocean is bounded on the west by North and South America. It connects to the Arctic Ocean through the Denmark Strait, Greenland Sea,
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