Quick Definition
glass
Strong's Definition
glass
Derivation: perhaps from the same as G5205 (ὑετός) (as being transparent like rain);
KJV Usage: glass
Thayer's Greek Lexicon
ὕαλος, ὑαλου, ὁ (probably allied with ὑει, ὑετός (which see); hence, 'rain-drop', Curtius, 9604; Vanicek, p. 1046; but others make it of Egyptian origin (cf. Liddell and Scott, under the word)), from Herodotus ((3, 24) who writes ὕελος; (cf. Winer's Grammar, 22)) down;
1. any stone transparent like glass.
2. glass: Rev_21:18; Rev_21:21.
Mounce Concise Greek Dictionary
ὕαλος hyalos 2x
a transparent stone, crystal; also, glass, Rev_21:18 ; Rev_21:21
Abbott-Smith Greek Lexicon
ὕαλος , -ου , ὁ ,
[in LXX : Job_28:17 ( H2137 ) * ;]
1. ( Hdt .) a clear transparent stone.
2. (from Plat . on) glass: Rev_21:18 ; Rev_21:21 .†
Moulton & Milligan — Vocabulary of the Greek NT
ὕαλος , ἡ [page 647]
glass. This Attic form is retained in the NT ( Rev_21:18 ; Rev_21:21 , cf. Job_28:17 ). For the adj. cf. P Oxy X. 1294 .6 (ii/iii A.D.) ὑάλαι λάγυνοι δ ὕγειαι , 4 glass flasks in sound condition. In P Fay 134 .4 (early iv/A.D.) the word is used of some hard transparent stone (Edd.). Note the irregular termination ὕαλας in P Lond 402 verso .13 (B.C. 152 or 141) (= II. p. 11), and the adj. ὑελοῦς in P Fay 1041 f . (late iii/A.D.) λαγύνων ὑελῶν μεικ̣[ρῶν ] πλευρῶν ὑελῶν δ̄ . See also Moulton Gr . ii. p. 67.
Liddell-Scott — Intermediate Greek Lexicon
ὕαλος ὕα^λος, ορ ὕελος, ὁ, ἡ, "a clear, transparent stone", used by the Egyptians to enclose their mummies in, "oriental alabaster", Hdt. "a convex lens of crystal", used as "a burning-glass", Ar. "glass", Lat. vitrum, Plat. : glass itself existed in the time of Hdt. , but was not called ὕαλος till Plato's time. [Etym: The word is said to be Egyptian. Others refer it to ὕω, as if the orig. sense were "raindrop."]
STEPBible — Tyndale Abridged Greek Lexicon
ὕαλος, -ου, ὁ
[in LXX: Job.28:17 (זְכוּכִית) * ;]
__1. (Hdt.) a clear transparent stone.
__2. (from Plat. on) glass: Rev.21:18, 21.†
(AS)