atrium
1. Antiquity: The large, open space within a building, which is envelopped by colonnades.2. Βyzantium: The forecourt of a church in early Christian, Byzantine, and medieval arcitecture. It was usually surrounded by four porticoes (quadriporticus).

coffer
Recessed ornamental square or octagonal panels sunk in the ceilings of buildings. They were decorated with relief or pictorial, usually floral, designs.

exedra, the
1. Large semicircular niche-like structure with stone seats ranged around the walls, often outdoors or with a hemidome over. An exedra may also be expressed by a curved break in a colonnade, perhaps with a semi-circular seat.2. The rectangular hall of the palaestra, open to the courtyard with columns at the front. The exedrae in gymnasium and palaestra could have served many functions. Usually a hall of such type was the Ephebeum.

peristyle
A colonnade surrounding a building or a courtyard .

terrace, the
Level surface made through landfills on reclining ground (e.g. on the slopes of mountains or hills), supported with the aid of retaining constructions (e.g. walls and buttresses), aiming at the creation of space suitable for the erection of buildings.

triclinium
Hall for symposia where three anaklintra were placed around the three sides of a square table. During the Late Roman period it was the main reception area of both houses and palaces (the term is maintained in the Byzantine era).