Abbott-Smith Manual Greek Lexicon
ἄ-σβεστος (G762)
3 ἄ-σβεστος , -ον ( σβέννυμι ), [in LXX for נפח לֹא , Jb 20:26 א 3 A ( ἄκαυστον , א 2 B)*;] unquenched , unquenchable : πῦρ , Mt 3:12 , Mk 9:43 , Lk 3:17 .†
G. Abbott-Smith, A Manual Greek Lexicon of the New Testament (1922) — public domain