dungeon has definitions from the field of medieval
1
[ noun ] (medieval) the main tower within the walls of a medieval castle or fortress

Synonyms

donjon keep

Used in print

(Chicago Daily Tribune...)

The vast , dungeon kitchens may seem hardly worth using except on occasions when one is faced with a_thousand unexpected guests for lunch .

(Louis Zara, Dark Rider....)

At the end of a shaft_of_light , the pews appeared to be broad stairs in a long dungeon .

2
[ noun ] a dark cell (usually underground) where prisoners can be confined

Related terms

cell oubliette

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