Definitions
1.nounAn underground prison or vault, typically built underneath a castle.
2.nounThe main tower of a motte or castle; a keep or donjon.
3.nounA shrewd person.
4.noun(games) An area inhabited by enemies, containing story objectives, treasure and bosses.
5.noun(BDSM) A room dedicated to sadomasochistic sexual activity.
6.verbTo imprison in a dungeon.