oubliette

/ˈubliˌɛt/

Other forms: oubliettes

For all you prison enthusiasts out there, the oubliette is like the Cadillac of dungeons. An oubliette is a specific type of dungeon that has only one escape route — through a trap door in its ceiling.

An oubliette is very well constructed from the captor's point of view. With the only entrance and exit being in the ceiling far above where the prisoner stands, escape is pretty much impossible. You may have seen oubliettes depicted in horror movies. As you may have guessed from the spelling, oubliette is a French word.

Definitions of oubliette

1. noun

   a dungeon with the only entrance or exit being a trap door in the ceiling
   type of:

   dungeon

   a dark cell (usually underground) where prisoners can be confined