Glossary

Abutment

In bridge construction, the landward approach to the bridge.

Adobe

Sun-dried brick, made of clay, water and a bonding material (e.g., straw).

Aggregate

Broken stone, gravel or sand that is mixed with cement and water to form concrete.

Agora

The open space in a Greek town used for markets and public gatherings; equivalent to the Roman forum.

Aisle

In churches, the space between the nave and the outer wall.

Almonry

In monasteries, the room in which alms are distributed.

Ambulatory

In churches, the continuation of the aisle around an apse; originally used for liturgical purposes.

Apse

In churches, the (usually) semicircular termination at the east end that often houses the altar.

Arcade

A free-standing row of arches supported on piers or columns.

Archimedes’ screw

A device comprising a spiral passage within an inclined closed cylinder, used for raising water; also Archimedean screw.

Ashlar

Squared blocks of smooth stone neatly trimmed to shape.

Atrium

An inner courtyard open to the sky or covered with a skylight.

Attic story

In classical architecture, a story above the main entablature.

Bailey

The courtyard inside castle walls; also known as a ward.

Barbican

The fortified gateway defending the drawbridge or entrance of a castle.

Barrel vault

The simplest form of vault, consisting of a series of semicircular arches extended prismatically.

Bas-Relief

Low-relief sculpture or carving, often applied as architectural decoration.

Bastion

A projecting tower at the angle of a fortification.

Battered wall

A wall with an inclined face.

Berm

An earthen mound or wall.

Béton brut

Concrete left unfinished except for the impression of the formwork on its surface; also known as “off-form” concrete.

Bevel

A right-angled corner cut off asymmetrically (i.e., at other than 45 degress). See Chamfer.

Breccia

A type of stone consisting of sharp fragments embedded in a fine-grained matrix.

Brise-Soleil

A sun protection device; a shading screen.

Buttress

A masonry support built against an exterior wall of a building to absorb lateral thrusts from roof vaults.

Caisson

A watertight chamber used in underwater construction work or as a foundation.

Cantilever

A horizontal projection from a building (e.g., a balcony, beam or canopy) that is without external bracing and appears to be self-supporting.

Capital

The head of a column.

Caravansary

An inn for the lodging of caravans; also caravanserai.

Caryatid

In classical Greek architecture, a sculptured draped female figure supporting an entablature.

Cast-iron

A hard, brittle and nonmalleable alloy of iron, carbon, and silicon cast in a mold.

Castellation

In castles, a battlement with alternating indentations and raised portions; also called crenellation.