aisle
Τhe part of the naos of a church set off by the internal rows of piers or columns, namely by the structures supporting the roof.

ambo
The elevated pulpit used for preaching in the church nave.

apse
An arched srtucture or a semi-circular end of a wall. In byzantine architecture it means the semicircular, usually barrel-vaulted, niche at the east end of a basilica. The side aisles of a basilica may also end in an apse, but it is always in the central apse where the altar is placed. It was separated from the main church by a barrier, the templon, or the iconostasis. Its ground plan on the external side could be semicircular, rectangular or polygonal.

architrave or epistyle
The lowest part of an entablature resting on the columns capitals and supporting the frieze.

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).

basilica
In ancient Roman architecture a large oblong type building used as hall of justice and public meeting place. The roman basilica served as a model for early Christian churches.

chancel screen of presbytery
A short barrier between the bema and the nave. It had originally the form of a parapet that was later made of stone or of marble. It is generally an element of early Christian religious architecture, and it appears on ground plans either as a linear structure or forming a Π. It consists of small columns or pillars in the interspace of which slabs are inserted. Crosses and floral patterns are usually used for the relief decoration of the screen.

dedicatory inscription
Inscription referring to a donation towards a church or an establishment. It sometimes includes the name of the donor, the type of subsidy (construction, restoration, wall paintings and donation), the time the subsidy was granted and other information as well.

dome
A characteristic element of Byzantine architecture. The dome is a hemispherical vault on a circular wall (drum) usually pierced by windows. The domed church emerges in the Early Byzantine years and its various types gradually prevail, while they are expanded in the Balkans and in Russia.

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.

gallery
The upper level of a house where the women resided. In ecclesiastical architecture it is the corridor above the aisles and narthex of a church, from where women attended the Liturgy. Originally (in the Byzantine period) the gallery, having a special entrance, was used exclusively by the emperor and the members of the royal family.

marble revetment
Τhe facing of a wall with slabs of marble

narthex
A portico or a rectangular entrance-hall, parallel with the west end of an early Christian basilica or church.