The ‘oubliette’ (pronounced “oo-blee-ett”) is a French term from the verb ‘oublier’ or ‘to forget’. It was so named, because a prisoner was thrown down into one, and then forgotten. An oubliette was a specialized type of dungeon, with the only entrance a trap door at the top, agonizingly out of reach of the prisoner.
Often this horrible prison was built as a very narrow passage, not wide enough for the prisoner to sit down or even get down on his knees. He was forced to stand as he starved to death, the sounds of the living all around him. He could tilt his head back to see the grate, far above his head and out of reach, but that was all.
The oubliettes were often built within the upper floors of a castle, rather than in the cellar so that victims could hear and smell the life of the castle as they slowly died of deprivation in unspeakable conditions. Corpses were left to be consumed by vermin, and many oubliettes were discovered, centuries later, to be strewn with human bones.