| 1. keep of a castle; underground prison, vault, cell. dungeondungeon , 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, common , under ground, as if the lower apartments of the donjon or keep of a castle, these being used as prisons. down with him even into the deep dungeon. -- tyndale. year after year he lay patiently in a dungeon. -- macaulay.dungeon dungeon, v. t. to shut up in a dungeon. hall.dungeon n |