Abyss

n. yawning chasm, immeasurable void; something unfathomable; abode of the dead, hell

Abyss may mean:Sciences and philosophyAbyssal zone, the deepest extent of the sea.Abyssal plain, a flat area on the ocean floor.Abyss (religion), is a bottomless depth.Abyss (Thelema), a spiritual principle within the system of Thelema.LiteratureThe Abyss (novel), historical novel by Marguerite Yourcenar, alternatively know as Zeno of Bruges. The Abyss, horror novel (1989) by U.S. writer Steve Vance.The People of the Abyss by Jack LondonThe Abyss, the deepest parts of the Timeless Halls in J. R. R. Tolkien's legendariumTV and moviesSpirit of the Abyss, from AndromedaThe Abyss, a 1989 science fiction deep-sea adventure movieAbyss (Stargate SG-1), a 6th-season episode of Stargate SG-1The Abyss (Entourage), an episode of the Entourage TV seriesAbyss (TV series), a 2002 BBC TV series in which live footage of life in the deep oceans was broadcast
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Noun
1. a bottomless gulf or pit; any unfathomable (or apparently unfathomable) cavity or chasm or void extending below (often used figuratively)
(synonym) abysm
(hypernym) chasm

(n.)
The center of an escutcheon.
  

(n.)
Infinite time; a vast intellectual or moral depth.
  

(n.)
A bottomless or unfathomed depth, gulf, or chasm; hence, any deep, immeasurable, and, specifically, hell, or the bottomless pit.
  

Abyss [from Greek a not + byssos, bythos deep, depth] Bottomless, unfathomable; chaos, space, the watery abyss which becomes the field of manifestation or cosmos -- a concept found in all mythologies. With the Sumerians, Akkadians, and Babylonians the great Deep gave birth to Ea, the All-wise, unknowable infinite deity, while in the Chaldean cosmogony Tiamat, the female principle, is the imbodiment of chaos. The Abyss or chaos was the abode of cosmic wisdom. Egyptian cosmogony speaks of Nut as the celestial abyss while Scandinavian cosmogony tells of Ginnungagap (chasm of offspring of Ginn), the infinite void or the abyss of illusion (SD 1:367).