1911 Encyclopædia Britannica/Abaddon
ABADDON, a Hebrew word meaning "destruction." In poetry it comes to mean "place of destruction," and so the underworld or Sheol (cf. Job xxvi. 6; Prov. xv. 11). In Rev. ix. 11 Abaddon (Άβαδδών) is used of hell personified, the prince of the underworld. The term is here explained as Apollyon (q.v.), the "destroyer." W. Baudissin (Herzog-Hauck, Realencyklopädie) notes that Hades and Abaddon in Rabbinic writings are employed as personal names, just as shemayya in Dan. iv. 23, shāmayim ("heaven"), and mākōm ("place") among the Rabbis, are used of God.