Lexical Definition

‎ᾅδης‎ háidēs (hah'-dace) hell: Hades ^G:N-M
from ‎Α‎ (as negative particle) and ‎εἴδω‎

grave, hell.

• properly, unseen, i.e. "Hades" or the place (state) of departed souls

Abbott-Smith

ᾅδης, -ου, ὁ [in LXX ehiefly for שְׁאוֹל, also for דּוּמָה, מָוֶת, etc.;]

1. in Hom., Hades (Pluto), the god of the underworld.
2. the abode of Hades, the underivorld; in NT, the abode of departed spirits, Hades: ἐν τ. ᾅ., Lk 16:23; εἰς ᾅ., Ac 2:27, 31; πύλαι ᾅδου, Mt 16:18; κλεῖς τοῦ ᾅ., Re 1:18; metaph., ἕως ᾅ., Mt 11:23, Lk 10:15; personified, Re 6:8 20:13, 14 (Cremer, 67, 610; MM, VGT, s.v.).†

Abbott-Smith References

Liddell-Scott-Jones

ᾍδης

or ᾅδης, ου, ὁ, Attic dialect; Epic dialect Ἀΐδης, α and ε; Doric dialect Αΐδας, α, used by Trag., in Lyric poetryand anapaest meter: genitive Αϊδος, dative Αϊδι, [Refs 8th c.BC+] only as proper name [Refs 8th c.BC+] —εἰν᾽ Αΐδαο δόμοισι in the nether world, [Refs 8th c.BC+]; frequently εἰν, εἰς Αΐδαο (i.e. δόμοις, δόμους), as [Refs 8th c.BC+]; Trag. and Attic dialect ἐν Ἅιδου, εἰς Ἅιδου (i.e. οἴκῳ, οἶκον), [Refs 5th c.BC+]; Ἄϊδόσδε, adverb to the nether world, [Refs 8th c.BC+]; παρ᾽ Ἅιδῃ, παρ᾽ Ἅιδην, [Refs] —hence,

__2 place of departed spirits, first in [NT+8th c.BC+]
__II after [Refs 8th c.BC+], the grave, death, ἀΐδαν λαγχάνειν, δέξασθαι, [Refs 5th c.BC+]; ᾅδης πόντιος death by sea, [Refs 5th c.BC+]; ᾅδου πύλη, Astrology texts, region below the Horoscope, [Refs 2nd c.AD+]
__II.2 genitive ᾅδου with nouns in adjectival sense, devilish, θύουσαν ᾅ. μητέρ᾽[Refs 5th c.BC+]; fatal, deadly, δίκτυον, ξίφη ᾅ., [Refs 8th c.BC+] in all forms except ᾱῐδος before vowels; ᾱῐδης [Refs 7th c.BC+]

_{LSJ Scripture Refs: Luke.16.23}