(declension-2, literally, neuter) inner shrine, sanctuary, Holy of Holies: (the innermost or most secret part of a temple or other sacred place; the sanctuary, which none but priests could enter, and from which oracles were delivered)
(broadly, declension-2, neuter) a secret place or chamber
(declension-2, neuter) a grave, tomb, or mausoleum
(declension-2, figuratively, neuter) the inmost recesses
Pronounced as (IPA)
[ˈa.dy.tũː]
Etymology
From the Ancient Greek ἄδῠτον (ádŭton, “innermost sanctuary”, “shrine”), a substantivisation of the neuter forms of the adjective ἄδῠτος (ádŭtos, “not to be entered”).