abyss
nounA bottomless gulf; used also for a deep mass of waters, supposed by some to have encompassed the earth before the flood. Darkness was upon the face of the deep, or abyss, as it is in the Septuagint. Genesis 1:2. The word is also used for an immense cavern in the earth, in which God is supposed to have collected all the waters on the third day of the creation. It is used also for hell, Erebus.