oubliette
/ubliˈɛt/Definitions
1. noun
a small, enclosed space, often a cell or dungeon, typically found in a castle or fortress, where prisoners were kept.
“The medieval castle had a notorious oubliette where captured enemies were thrown to their deaths.”
2. noun
a place of confinement or imprisonment.
“The politician was accused of operating a secret oubliette where suspects were detained without trial.”