1769, The Bible, King James Version, Oxford Standard Text, 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.

Lipsius was replaced at Leyden by Joseph Justus Scaliger (1540-1609), the French Protestant scholar who was known to contemporaries as "the bottomless pit of erudition."

2006: The Club For Growth: Bottomless Pit (blog entry), Phillip Rodokanakis
In other words, we will continue throwing good money after bad, trying to feed a bottomless pit's insatiable appetite for taxpayer dollars.

Bottomless pit

Meaning

Noun

Synonyms