Destroyer, the name given to the king of the hosts represented by the locusts (Rev. 9:11). It is the Greek translation of the Hebrew Abaddon (q.v.).
Apollyon
1 verse
Revelation
Revelation 9:11
And they had a king over them, which is the angel of the bottomless pit, whose name in the Hebrew tongue is Abaddon, but in the Greek tongue hath his name Apollyon.
From Easton's Bible Dictionary
Matthew George Easton, 1897
From Smith's Bible Dictionary
William Smith, 1884
or, as it is literally in the margin of the Authorized Version of (Revelation 9:11) "a destroyer," is the rendering of the Hebrew word ABADDON, "the angel of the bottomless pit." From the occurrence of the word in (Psalms 88:11) the rabbins have made Abaddon the nethermost of the two regions into which they divide the lower world; but that in (Revelation 9:11) Abaddon is the angel and not the abyss is perfectly evident in the Greek.