abyss

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

(frequently figurative) 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.