Oubliette

Oubliette, an underground cell, perfectly dark, in which prisoners were subjected to perpetual confinement, was so called as being a “place of forgetfulness,” or where one is forgotten; they were often put secretly to death.

Definition taken from The Nuttall Encyclopædia, edited by the Reverend James Wood (1907)

Otway, Thomas * Oudenarde
Othman
Otho
Otis, James
Otranto
Ottawa
Ottawa River
Otterburn
Otto
Ottomans
Otway, Thomas
Oubliette
Oudenarde
Oudh
Oudinot, Duke of Reggio
Ouida
Ouse
Outram, Sir James
Overbeck, Friedrich
Overbury, Sir Thomas
Overland Route
Overreach, Sir Giles