Albert Barnes Commentary Jeremiah 37:16

"When Jeremiah was come into the dungeon-house, and into the cells, and Jeremiah had remained there many days;" — Jeremiah 37:16 (ASV)

Dungeon - literally, house of a cistern or pit, and evidently underground. In this cistern-like excavation were several cells or arched vaults, in one of which with little light and less ventilation Jeremiah remained a long time.