Atrium

Atrium, in Roman Architecture, was the hall which formed the chief part of a Roman house; into it one entered from the vestibule by the main door. It was lighted from the roof, which sloped towards an opening in the centre (the compluvium), through which the rain-water flowed into a kind of cistern situated on the floor (the impluvium). On both sides, passages led to the several chambers, and behind it was the roofless cavedium. In early Rome, the family gods and the nuptial couch stood in the atrium, which was used as the common public apartment, where the mistress and her maids sat spinning; but in later times it was reserved as a general waiting-room for visitors and clients.—In ecclesiastical architecture, the atrium was an open court before a church, where penitents and others stood to solicit the prayers of the faithful.