Extended Strong's Greek Lexicon (Abbott-Smith based)
Abaddon
Usage: Ἀβαδδών (Heb. אֲבַדּוֹן, destruction; LXX, ἀπώλεια, only in Wisdom Lit., of the place of the ruined dead: Job.26:6, 28:22, 31:12, Psa.88:12, Pro.15:11*), indecl.; in NT, Abaddon, the angel of the Abyss: Rev.9:11.† (AS)