layer - a relatively thin sheetlike expanse or region lying over or under another

body of water, water - the part of the earth's surface covered with water (such as a river or lake or ocean); "they invaded our territorial waters"; "they were sitting by the water's edge"

Earth, globe, world - the 3rd planet from the sun; the planet on which we live; "the Earth moves around the sun"; "he sailed around the world"

briny, main - any very large body of (salt) water

ocean - a large body of water constituting a principal part of the hydrosphere

sea - a division of an ocean or a large body of salt water partially enclosed by land