Oubliettes are typically described as dungeons or underground vaults used to imprison people. However, there are a few lesser-known synonyms for this word, such as "dungeons delitescence," which refers to hidden dungeons. Other words include "oubliers," which means one who forgets or forgetters, and "oubliance," referring to the act of forgetting or neglecting something. Another synonym for oubliettes is "vau-de-vire," a term used in French to describe a trapdoor or a secret passage leading to a dungeon. Additionally, "oubliance holes" is another synonym used to describe small, dark spaces in castles or forts where prisoners were kept. Despite the various words used to describe oubliettes, they all embody the same terrifying, inhumane nature of the medieval prison system.