Typical Early Christian/Byzantine apse with a hemispherical semi-dome.

This article is about an architectural feature; for the astronomical term see apsis. For the rock band, see Apse (band). Or you may mean the acronym APS.

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In architecture, the apse (Greek αψις (apsis), then Latin absis: "arch, vault"; sometimes written apsis; plural apses) is a semicircular recess covered with a hemispherical vault or semi-dome. In Romanesque, Byzantine and Gothic Christian abbey, cathedral and church architecture, the term is applied to a semi-circular or polygonal termination of the main building at the liturgical east end (where the altar is), regardless of the shape of the roof, which may be flat, sloping, domed, or hemispherical.

Definition[link]

The apse is the semicircular or polygonal termination to the choir or aisles of a church. In relation to church architecture it is generally the name given to where the altar is placed or where the clergy are seated.^[1]

The epithet "apsidal" may be applied to the exedra of classical architecture, a feature of the secular Roman basilica.

Features[link]

The apse as a semicircular projection (which may be polygonal on the exterior, or reveal the radiating projections of chapels) may be roofed with a semi-dome (also called a half-dome) or with radiating vaulting. A simple apse may be merely embedded within the wall of the east end. Eastern orthodox churches may have a triple apse, which is usually a mark of Byzantine influence when it is seen in Western churches.

Smaller subsidiary apses may be found around the choir or at the ends of transepts. These proliferating apses are common in later Byzantine architecture and the Ottoman architecture that developed from it. The term "abse" tends to be reserved for those at the liturgical east end, with these further spaces called "exhedras" or "absidal openings". A tetraconch is a church on a central plan with four abses, one in each direction. An exedra or apse may be reduced in scale to form a niche within the thickness of walling; a niche does not reveal its presence by projecting on the exterior.

Related features[link]

In the Eastern Orthodox tradition, the south apse is known as diaconicon and the north apse as prothesis. Various ecclesiastical features of which the apse may form part are drawn together here:

Presbytery[link]

The presbytery (or sanctuary), directly to the east beyond the choir is the High Altar, where there is one (compare communion table). This area is reserved for the clergy. The word derives from the Greek presbuteros meaning "elder".

Chevet[link]

In the beginning of the 13th century in France, the apses were built as radiating chapels outside the choir aisle, henceforth known as the chevet (French, "headpiece"), when the resulting structure was too complicated to be merely an "apse". Famous northern French examples of chevets are in the Gothic cathedrals of Amiens, Beauvais and Reims. Such radiating chapels are found in England in Norwich and Canterbury cathedrals, but the fully developed feature is essentially French, though the Francophile connoisseur Henry III introduced it into Westminster Abbey.

Ambulatory[link]

The word "ambulatory" refers to a curving aisle in the apse that passes behind the altar and choir, giving access to chapels in the chevet. An "ambulatory" ("walking space") may refer to the arcade passages that enclose a cloister in a monastery, or to other types of aisles round the edge of a church building, for example in circular churches.

See also[link]

Look up apse in Wiktionary, the free dictionary.

Wikimedia Commons has media related to: Apses

• Architectural development of the eastern end of cathedrals in England and France
• Byzantine architecture
• Cathedral architecture
• Cathedral architecture of Western Europe
• Chancel repair liability in the United Kingdom
• Church architecture
• Narthex

References[link]

• Joseph Nechvatal, "Immersive Excess in the Apse of Lascaux", Technonoetic Arts 3, no3. 2005

Gallery[link]

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  Triple apse of Basilica di Santa Giulia, northern Italy.

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  East end of the abbey church of Saint-Ouen, showing the chevet, Rouen, Seine-Maritime.

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  A chevet apse vault.

• St chads in poulton-le-fylde.jpg

  A simple apse set into the east end of St Chad's parish church, at Poulton-le-Fylde, Lancashire.

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  The decorated apses of the Cathedral of Monreale, Sicily.

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  The apse of St. Martin church in Busskirch, community Jona, Switzerland.

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  Apse for Torah Ark in the ancient Maon Synagogue.

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  The triple apse of an Orthodox church.