ETYM Latin abyssus a bottomless gulf, from Greek for bottomless; a priv. + byssos depth, bottom.
(Irregular plural: abysses).
A bottomless gulf or pit; SYN. abysm.
Any unfathomable (or apparently unfathomable) cavity or chasm or void extending below (often used figuratively)

ETYM Latin chasma, Greek, from chainein to gape, to open wide. Related to Chaos.
A deep opening in the earth's surface.

ETYM French golfe, Italian golfo, from Greek kolpos bosom, bay, gulf.
1. A deep wide chasm.
2. An arm of a sea or ocean partly enclosed by land; larger than a bay.
3. An unbridgeable disparity (as from a failure of understanding).
Any large sea inlet.

ETYM French précipice, Latin praecipitium, from praeceps, -cipitis, headlong; prae before + caput, capitis, the head. Related to Pre-, and Chief.
1. A very steep or overhanging place, a very steep cliff.
2. A hazardous situation; broadly; brink.

gulf