dungeon

n. keep of a castle; underground prison, vault, cell

This is about European castles. For other uses see Dungeon (disambiguation) A dungeon is a place where prisoners are kept. In the past, it used to double as the keep.
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Dungeon! is a 1975 adventure board game designed by David R. Megarry, Gary Gygax, Michael Gray, Steve Winter and S. Schwab, published by TSR, Inc.  Dungeon! simulates some aspects of the Dungeons & Dragons (D&D) role-playing game which was released the year before, although Dungeon! was already in development when D&D was released.
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Noun
1. the main tower within the walls of a medieval castle or fortress
(synonym) keep, donjon
(hypernym) stronghold, fastness
(hyponym) Black Hole of Calcutta
(part-holonym) castle
2. a dark cell (usually underground) where prisoners can be confined
(hypernym) cell, jail cell, prison cell
(hyponym) oubliette

(v. t.)
To shut up in a dungeon.
  

(n.)
A close, dark prison, common/, under ground, as if the lower apartments of the donjon or keep of a castle, these being used as prisons.
  

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