What is the meaning of Abyss?

Hell; the bottomless pit; primeval chaos; a confined subterranean ocean.

A bottomless or unfathomed depth, gulf, or chasm; hence, any deep, immeasurable; any void space.

Anything infinite, immeasurable, or profound.

Moral depravity; vast intellectual or moral depth.

An impending catastrophic happening.

The center of an escutcheon.

The abyssal zone.

A difference, especially a large difference, between groups.

Source: wiktionary.org