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						AbacusFlat top of the capital of a column.
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						AbbeyMain or sole church built in conjunction with an abbey
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						AbbeyA building inhabited by a community of monks or nuns governed by an autonomous leader
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						AbutmentSolid masonry placed to counteract the lateral thrust of a bridge, arch, or vault.
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						AltarA structure on which to place or sacrifice offerings to a deity. In a Christian church the altar is usually a stone table or slab on supports, on which the celebration of the sacrament takes place.
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						AlureA passage or gallery behind a parapet at the top of a wall of a fortification.
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						AmbulatoryA semicircular or polygonal aisle. Often an ambulatory leads around the east end of the choir.
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						ApseThe semi-circular termination of the east end of the chancel or chapel.
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						ApsidioleSemi-circular chapel (in the transept or chancel) or secondary apse .
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						ArcadeA series of arches supported by columns or piers.
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						ArcatureSeries of small arcades topped by an arch.
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						ArchA carved structural member that spans an opening.
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						Arch mouldingConcentric arches set back from one another above a doorway or a window and topped by the archivolt.
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						ArchitraveThe beam which extends across the top of the columns; it forms the lowest part of the entablature.
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						ArchivoltSet of arches rising above a doorway. In the Romanesque and gothic styles, the archivolt frames the tympanum, a richly sculpted panel.
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						Arms of a transeptSections of the transept on each side of the crossing.
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						AstragalA small plain or ornamental moulding.
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						AtticA room, usually with sloping ceilings, just beneath the roof
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						Avant-corpsPart of a building which projects prominently from the main facade.

