Quick Definition
the abyss, the unfathomable depth
Strong's Definition
depthless, i.e. (specially) (infernal) "abyss"
Derivation: from G1 (Α) (as a negative particle) and a variation of G1037 (βυθός);
KJV Usage: deep, (bottomless) pit
Thayer's Greek Lexicon
ἄβυσσος, in classic greek an adjective, (ος, (from ὁ βύσσος equivalent to βυθός), bottomless (so perhaps in Wis_10:19), unbounded (πλοῦτος ἄβυσσος, Aeschylus, the Sept. (931) 950). in the Scriptures ἡ ἄβυσσος (the Sept. for ϊΐΜδεν) namely, χώρα, the pit, the immeasurable depth, the abyss. Hence, of 'the deep' sea: Gen_1:2; Gen_7:11; Deu_8:7; Sir_1:3 Sir_16:18, etc.; of Orcus (a very deep gulf or chasm in the lowest parts of the earth: Psalms 70:20 () ἐκ τῶν ἀβύσσων τῆς γῆς, Euripides, Phoen. 1632 (1605) ταρτάρου ἄβυσσα χάσματα, Clement of Rome, 1Cor. 20:5 [ET] ἀβύσσων ἀνεξιχνίαστα κλίματα, ibid. 59, 3 [ET] ὁ ἐπιβλέπων ἐν ταῖς ἀβύσσοις, of god; (Act. Thom.32ὁ τήν ἄβυσσον τοῦ ταρτάρου οἴκων, of the dragon)), both as the common receptacle of the dead, Rom_10:7, and especially as the abode of demons, Luk_8:31; Rev_9:1; Rev_9:11; Rev_11:7; Rev_17:8; Rev_20:1; Rev_20:3. Among secular authors used as a substantive only by Diogenes Laërtius 4 (5) 27 κατῆλθες εἰς μέλαιναν Πλουτέως ἄβυσσον. Cf. Knapp, Scripta var. Arg., p. 554f; (J. g. Müller, Philo's Lehre von der Weltschöpfung, p. 173f; B. D. American edition under the word ).
Mounce Concise Greek Dictionary
ἄβυσσος abyssos 9x
bottomless; place of the dead,
Luk_8:31 ; Rom_10:7
Abbott-Smith Greek Lexicon
ἄ -βυσσος , -ον
(
Moulton & Milligan — Vocabulary of the Greek NT
ἄβυσσος [page 1]
As a substantive ( Rom_10:7 , Rev_9:1 etc.) ἄ . is common in the magic papyri, e.g. P Lond 121 .261 (iii/A.D.) ( = I. p. 93) ἐπὶ τῆς ἀβύσσου , ib. .517 ( = I. p. 100) τῇ καλουμένῃ ἀβύσσῳ . See also Nδgeli, p. 46.
Liddell-Scott — Intermediate Greek Lexicon
ἄβυσσος [Etym: For the Root, v. βαθύς.] "with no bottom, bottomless, unfathomed", Hdt. ; generally, "unfathomable, enormous", Aesch. ἡ ἄβυσσος, "the great deep, the abyss, bottomless pit", NTest.
STEPBible — Tyndale Abridged Greek Lexicon
ἄ-βυσσος, -ον (Ion. βυσσός = βυθός),
__1. in cl., boundless, bottomless (e.g. ἄ. πέλαγος, ἄ. πλοῦτος Æsch.).
__2. [In LXX (for תְּהוֹם, Gen.1:2, al.; exc. Isa.44:27, Job.41:22 for צוּלָה, מְצוּלָה, Job.36:16 for רַחַב) and] NT, as subst. (MM, VGT, see word), ἡ ἄ. (sc. χώρα), the abyss;
__(a) of the sea (Gen.1:2);
__(b) of the underworld, as the abode of the dead: Rom.10:7 (a paraphrase of Deu.30:13 LXX); as the abode of demons, Luk.8:31, Rev.9:1, 2, 11, 11:7, 17:8, 20:1, 3 (Cremer, 2).
† (AS)