The Hebrew word Abaddon (H111) is derived from abad (H6), meaning "to perish" or "to destroy." It refers to a place of destruction — the realm of the dead — and occurs six times in the Old Testament.
In the New Testament, the name appears in Revelation 9:11 as the name of the angel of the Abyss, transliterated in Greek as Apollyon (destroyer).
In Hebrew poetic literature, Abaddon is personified as the depths of Sheol — the place beyond death, a realm of ruin and silence. Job and the Wisdom literature use it to emphasize the omniscience of God who sees even into the abyss of destruction.
Theologically, the word underscores God's absolute sovereignty: even the place of ultimate destruction lies open before Him (Proverbs 15:11). No depth — physical or spiritual — is hidden from the Lord.