Quick Definition
ἄβυσσος, ου, ἡ n.f. the abyss, the unfathomable depth
Strong's Definition
from 1 (as a negative particle) and a variation of 1037; depthless, i.e. (specially) (infernal) "abyss"
KJV Usage: deep, (bottomless) pit
UBS Dictionary of the Greek New Testament
noun, f. | -ου | ἀ- + βυθίζω
1.20 · Geographical Objects and Features · Regions Below the Surface of the Earth
abyss, abode of evil spirits, very deep place (a figurative extension of meaning of ἄβυσσος ‘pit,’ not occurring in the NT) a location of the dead and a place where the Devil is kept (REV 20:3), the abode of the beast as the antichrist (REV 11:7), and of Abaddon, as the angel of the underworld (REV 9:11) ἄβυσσος is sometimes rendered as ‘a very deep hole’; in other instances, ‘a hole without a bottom’ or ‘the deepest hole in the earth.’
LUK 8:31 · ROM 10:7 · REV 9:1 · REV 9:2 · REV 9:11 · REV 11:7 · REV 17:8 · REV 20:1 · REV 20:3
UBS Dictionary of the Greek New Testament © United Bible Societies, licensed CC BY-SA 4.0.
Thayer's Greek Lexicon
ἄβυσσος, in classic Greek an ad/j., -os, τον, (fr. 6 βυσσός i. q. βυθός), bottomless (so perhaps in Sap. x. 19), unbounded (πλοῦτος ἄβυσσος, Aeschyl. Sept. (931) 950). In the Scriptures ἡ ἄβυσσος (Sept. for DITA) se. χώρα, the pit, the immeasurable depth, the abyss. Hence of ‘the deep’ sea: Gen. i. 2; vii. 11; Deut. viii. 7; Sir. i. 3; xvi. 18, ete.; of Orcus (a very deep gulf or chasm in the lowest parts of the earth: Ps. xx. (1xxi.) 21 ἐκ τῶν ἀβύσcoy τῆς γῆς, Eur. Phoen. 1632 (1605) raprapov ἄβυσσα χάσματα, Clem. Rom. 1 Cor. 20, 5 ἀβύσσων ἀνεξιχνίαστα κλίματα, ibid. 59, 3 6 ἐπιβλέπων ἐν ταῖς ἀβύσσοις, of God; [Act. Thom. 32 ὁ τὴν ἄβυσσον τοῦ ταρτάρου οἰκῶν, of the ἀγασοη 7), both as the common receptacle of the dead, Ro. x. 7, and especially as the abode of demons, Lk. viii. 31; Rev. ix. 1 sq. 11; xi. 7; xvii.8;xx.1,3. Among prof. auth. used as a subst. only by Diog. Laért. 4, (5,) 27 κατῆλes εἰς μέλαιναν Πλουτέως ἄβυσσον. Cf. Knapp, Scripta var. Arg. p.554 sq.; [J. G. Miiller, Philo’s Lehre von der Weltschépfung, p. 173 sq.; B. D. Am. ed. 5. v. Deep].” “AyaBos(on the breathing see WH. Intr. § 408], -ου, ὁ, the name of a Christian prophet, Agabus: Acts xi. 28; xxi. 10. (Perhaps from 23p to love [ef. B. Ὁ. 8. v.].)
Mounce Concise Greek Dictionary
ἄβυσσος abyssos 9x
bottomless; place of the dead, Lk. 8:31; Rom. 10:7
Abbott-Smith Greek Lexicon
ἄ-βυσσος, -ον
(< Ion. βυσσός = βυθός),
in cl., boundless, bottomless (e.g. ἄ. πέλαγος, ἄ. πλοῦτος Æsch.).
[In LXX (for תְּהוֹם, Ge 1:2, al.; exc. Is 44:27, Jb 41:22 for צוּלָה, מְצוּלָה, Jb 36:16 for רַחַב) and] NT, as subst. (MM, VGT, s.v.), ἡ ἄ. (sc. χώρα), the abyss; of the sea (Ge 1:2);
of the underworld, as the abode of the dead: Ro 10:7 (a paraphrase of De 30:13 LXX); as the abode of demons, Lk 8:31, Re 9:1, 2, 11, 11:7, 17:8, 20:1, 3 (Cremer, 2).†
Moulton & Milligan — Vocabulary of the Greek NT
ἄβυσσος. As a substantive (Rom τοῦ, Rev οἱ etc.) & is common in the magic papyri, e.g. P Lond 121° (iii/a.p.) (=I. p. 93) ἐπὶ τῆς ἀβύσσου, 7.17 (=I. p. 100) τῇ καλουμένῃ ἀβύσσῳ. See also Nageli, p. 46.
Liddell-Scott-Jones — Greek-English Lexicon
ἄβυσσος (abussos) — abyss. ἄβυσσος, ον, bottomless, unfathomed, πηγαί[Refs 5th c.BC+]: generally, unfathomable, boundless, πλοῦτος[Refs 5th c.BC+]
II. ἡ ἄ. the great deep, [LXX]: the abyss, underworld, [NT]; the infinite void, [Refs]