dungeon (dŭnjŭn), n. [OE. donjoun highest tower of a castle, tower, prison, F. donjon tower or platform in the midst of a castle, turret, or closet on the top of a house, a keep of a castle, LL. domnio, the same word as LL. dominus lord. See Dame, Don, and cf. Dominion, Domain, Demesne, Danger, Donjon.] A close, dark prison, commonly, under ground, as if the lower apartments of the donjon or keep of a castle, these being used as prisons.
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Down with him even into the deep dungeon. Tyndale.
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Year after year he lay patiently in a dungeon. Macaulay.
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