1. A bottomless or unfathomed depth, gulf, or chasm; hence, any deep, immeasurable, and, specifically, hell, or the bottomless pit. Ye powers and spirits of this nethermost abyss. (Milton) The throne is darkness, in the abyss of light. (Dryden)
3. The center of an escutcheon.
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.