Kitto's Popular Cyclopedia of Biblial Literature
Abad´don, or Apollyon (destruction). The former is the Hebrew name, and the latter the Greek, for the angel of death, described (Revelation 9:11) as the king and chief of the Apocalyptic locusts under the fifth trumpet, and as the angel of the abyss or 'bottomless pit' [HADES].
Kitto, John, ed. Entry for 'Abaddon'. "Kitto's Popular Cyclopedia of Biblial Literature". https://www.studylight.org/encyclopedias/eng/kbe/a/abaddon.html.