[1] : The Collaborative International Dictionary of English v.0.48

abyss \abyss"\, n. l. abyssus a bottomless gulf, fr. gr. ?
   bottomless; 'a priv. + ? depth, bottom.
   1. a bottomless or unfathomed depth, gulf, or chasm; hence,
      any deep, immeasurable, and, specifically, hell, or the
      bottomless pit.
      1913 webster

            ye powers and spirits of this nethermost abyss.
                                                  --milton.
      1913 webster

            the throne is darkness, in the abyss of light.
                                                  --dryden.
      1913 webster

   2. infinite time; a vast intellectual or moral depth.
      1913 webster

            the abysses of metaphysical theology. --macaulay.
      1913 webster

            in unfathomable abysses of disgrace.  --burke.
      1913 webster

   3. her. the center of an escutcheon.
      1913 webster

   note: this word, in its leading uses, is associated with the
         cosmological notions of the hebrews, having reference
         to a supposed illimitable mass of waters from which our
         earth sprung, and beneath whose profound depths the
         wicked were punished. --encyc. brit.
         1913 webster

[2] : WordNet (r) 2.0

abyss
     n : a bottomless gulf or pit; any unfathomable or apparently
         unfathomable cavity or chasm or void extending below
         often used figuratively syn: abysm
see also:
abysm 

[3] : Moby Thesaurus II by Grady Ward, 1.0

110 moby thesaurus words for "abyss":
   bassalia, gehenna, sheol, tophet, abysm, abyssal zone, arroyo,
   bathyal zone, benthos, bottom waters, bottomless depths,
   box canyon, breach, break, canyon, cavity, chap, chasm, check,
   chimney, chink, cleft, cleuch, clough, col, coulee, couloir, crack,
   cranny, crater, crevasse, crevice, cut, cwm, deep, deepness,
   defile, dell, depth, dig, diggings, dike, ditch, donga, draw,
   excavation, fault, fissure, flaw, flume, fracture, furrow, gap,
   gape, gash, gorge, groove, ground, gulch, gulf, gully, hades, hole,
   hollow, incision, inferno, inner space, joint, kloof, leak, mine,
   moat, netherworld, notch, nullah, ocean bottom, ocean depths,
   ocean floor, opening, pass, passage, pelagic zone, perdition, pit,
   profoundness, profundity, quarry, ravine, rent, rift, rime,
   rupture, scissure, seam, shaft, slit, slot, split, the deep,
   the deep sea, the deeps, the depths, trench, underworld, valley,
   void, wadi, well, workings, yawning abyss

Abyss >> A Words
Abyss, definition of term: Abyss
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