A — 1: κατωτέρω
(Strong's #2736 — — kato — kat'-o, kat-o-ter'-o )

for this see BENEATH.

B — 1: ἄβυσσος
(Strong's #12 — Noun Feminine — abussos — ab'-us-sos )

"bottomless" (from a, intensive, and bussos, "a depth"), is used as a noun denoting the abyss (AV, "bottomless pit"). It describes an immeasurable depth, the underworld, the lower regions, the abyss of Sheol. In Romans 10:7 , quoted from Deuteronomy 30:13 , the abyss (the abode of the lost dead) is substituted for the sea (the change in the quotation is due to the facts of the death and resurrection of Christ); the AV has "deep" here and in Luke 8:31; the reference is to the lower regions as the abode of demons, out of which they can be let loose, Revelation 11:7; 17:8; it is found seven times in the Apocalypse, 9:1,2,11; 11:7; 17:8; 20:1,3; in 9:1,2 the RV has "the pit of the abyss." See DEEP.