From a form of an obsolete primary chao (to "gape" or "yawn"); a "chasm" or vacancy (impassable interval) -- gulf.
Thayer's Greek Lexicon
Strong's 5490: χάσμα
χάσμα, χασματος, τό (χαίνω to yawn), a gaping opening, a chasm, gulf: equivalent to a great interval, Luke 16:26. (Hesiod theog. 740; Euripides, Plato, Plutarch, Lucian, Aelian, others.)
Luke 16:26 - N-ANS GRK:καὶ ὑμῶν χάσμα μέγα ἐστήρικται NAS: us and you there is a great chasm fixed, KJV: there is a great gulf fixed: so that INT: and you a chasm great has been fixed
