SAH Archipedia uses terms from the Getty Art and Architecture Thesaurus (AAT) to categorize and classify metadata for the entries in the database. For more information on the Getty AAT, click here

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backing brick

A relatively low-quality brick used behind face brick or other masonry.


The residue left after grinding sugarcane and extracting the juice, employed in making paper and fiber building board.

baked enamel

A hard, glossy coating of paint that is baked dry in an oven at 180 degrees. Baked enamel is usually used to coat metallic surfaces in industrial applications such as sign-making or the construction of household appliances.


Railed platforms projecting from the exterior walls of buildings. Use also for similar interior features, when small. For larger platforms which extend the length of one side of a room or are recessed behind an arcade, use "galleries (upper level spaces)."

ballast (aggregate)

Heavy material, such as water, sand, or iron, used to increase weight, as in a machine.

balloon frames

Wooden frameworks in which all vertical structural elements, posts and studs, of the exterior bearing walls and partitions extend the full height of the frame from sill to roof plate.

balsa (wood)

The wood of a fast-growing tropical bombaceous tree that is the lightest and softest wood used commercially. The white to tan-color, soft wood has a straight grain, coarse texture and is relatively strong. Balsa wood is easily carved and often used for model airplanes and toys. Balsa is also used as a substitute for cork in insulation, flats, life preservers, and buoys.

balsam (resin)

An oleoresinous exudate from coniferous trees, especially of the Pinus genus. Balsams have been used since antiquity for medicinal purposes and as sealers. The exudate is a soft, semi-liquid consisting of terpenes of resinous character and a large amount of essential oils. Upon distillation, a liquid portion, called turpentine, and a solid residue, called rosin, are produced. Balsams have been used in varnishes and paint mediums; however, they deteriorate easily unless a harder resin is mixed with them.

bamboo (material)

Material derived from the stem or stalk of the bamboo plant, which is any of 480 species of woody or treelike tropical and semitropical grass.

bamboo (plant)

General term for any of around 480 species of woody or treelike tropical and semitropical grasses of various genera, including Bambusa, Phyllosyachys, Dendrocalamus, and allied genera, all having woody, hollow stems, stalked blades, and flowering only after years of growth. Bamboo has been used locally for constructing houses, rafts, poles, bridges, and scaffolding. In Europe and America, bamboo stems were popular for chairs, tables, cabinets, and other interior furniture during the 19th century. They are also split, flattened and woven into smaller items such as baskets, mats, hats, and fish traps. Bamboo has also become an important source of long, cellulose fibers for specialty papers. Additionally, a wax is extracted from the bamboo leaves.

banco (clay)

Shaped, beaten clay used for making granaries.

banded slate

Slate that is distinguished by the light colored stripes or ribbons running through it. It was prized as a material in bannerstones and other ancient American ceremonial objects. When used in construction, it is known for being less durable than other slates because the ribbons are weaker than the surrounding dark areas.

barbed wire

Wire furnished with barbs or sharp hook or points spaced at regular intervals; typically used for fencing or other barriers, it may be of single or multiple intertwined strands.

bark (plant material)

The external material that covers the woody parts of trees, as distinct and separate from the wood itself.

bark strip

Material comprising strips of tree bark.

Barre granite

A type of gray granite quarried in Barre, Vermont, a center of granite quarrying in the U.S. since just after the War of 1812.

bas-reliefs (sculpture)

Refers to works executed in relatively shallow relief.

basalt (basic igneous rock)

A dense, hard, dark brown-to-black volcanic igneous rock, consisting of feldspar and mafic minerals such as augite or olivine.

basic igneous rock

Igneous rocks as classified according to chemical or mineralogical parameters, having low silica and typically high iron - magnesium content; examples are gabbro and basalt.

Batesville marble

Limestone from Arkansas, gray or cream colored.

batten (wood products)

In the context of wood products for carpentry and building, battens are pieces of squared timber of certain dimensions: not more than 7 inches broad and 2 1/2 inches thick, and over 6 feet long. Examples of use of battens includes for flooring, furring, supports for laths, or as cross pieces to secure the joint between two parallel boards.

bay windows

Windows, either single or in a series, forming a bay or recess in a room and projecting outward from the wall in a rectangular, curved, or polygonal form.

beading (edging pattern)

Enrichment consisting of a line of tiny beads; common on silver and furniture.

beak (material)

Material derived from the bill of a bird or similar horny mouthpart in other animals, such as the squid.

beech (wood)

Pale reddish-brown, close-grain wood from any of several trees of the genus Fagus; it is hard and heavy, bends well, is durable under water, and gives a smooth shiny finish. Beech wood is commonly used for flooring, cabinetry, furniture (especially bentwood chairs), veneer, plywood, tool handles, and turnery. It was used in panel paintings in western Europe.

Belgian black marble

A dense, hard marble from Belgium, considered the best black marble for carving due to its deep color and lack of veins and streaks.

Belgian block

A type of paving stone generally cut in a slightly pyramidal shape, laid with the base of the pyramid down.

Belgian linen
No description is available for this term.


A soft plastic light-colored clay formed by the chemical alteration of volcanic ash; it can swell to several times its original volume when placed in water.


Wood that is formed by bending rather than being cut into shape.

Betula (genus)

Genus of hardy, deciduous trees of the family Betulaceae, common to North America, Europe and Asia. Birch tress are readily distinguished by their white bark and diamond-shaped leaves. The lightweight bark contains natural waxes, oils, and tannins that make it tough, durable, and waterproof. Thin sheets of bark were commonly used for paper in Central Asia and the Far East. The water-impervious bark was used for wigwams, canoes, and shoes for Native Americans. Birch produces a strong, pale yellow-brown wood with a close, straight grain and uniform texture that finishes to a smooth surface. Dyes can also be obtained from various parts of birch trees. The leaves, usually gathered before they develop a mature green color, produce a yellow dye. The bark produces a pale brown color. The female catkins (a long shoot bearing flowers with no leaves) are boiled to produce a dull yellow color. Birch bark oil and birch beer are made from sap obtained from the trees. The sap allows birch bark to burn even when it is wet.

Betula nigra (species)

Species of ornamental tree found on riverbanks and swamps in the eastern one-third of the United States, growing 18-30 m (60 to 80 feet) in height. Because the lower trunk becomes very dark with age, the tree is sometimes called black birch. The red-brown, deeply furrowed bark on an old trunk breaks into ragged, closely appressed scales; the upper trunk and branches are smooth, salmon pink to rose cinnamon, with a metallic luster.

bigleaf maple (wood)

Wood of the species Acer macrophyllum, the only species native to the western United States. This commercially valuable wood is darker than that of other maples; used in the manufacture of furniture, piano actions, turnery, and musical instruments.

binder (material)

Any substance that produces or promotes cohesion among loosely assembled materials; also includes the substance in a photograph or photographic film that holds the final image material. For the combined material of photographic binder and image material, use "emulsion."

birch (wood)

Strong, pale yellow-brown wood from trees of the genus Betula, having a close, straight grain and uniform texture that finishes to a smooth surface. It is sometimes dyed to imitate mahogany. Birch is used for tools handles, plywood, hoops, shoe heels, flooring, furniture, cabinetry, turnery, and firewood. The bark is also used for various purposes.

bird's-eye maple

Maple wood with grain having a wavy, circular pattern with a central spot that resembles the eye of a bird. Used for veneers and furniture.

bituminous coal

A relatively soft coal containing the tarlike substance asphaltic bitumen. Its carbon content is 60-80%, the rest composed of water, air, hydrogen, and sulfur. It is of higher quality than lignite coal but of poorer quality than anthracite. It was usually formed as a result of high pressure on lignite. It dark brown to black in color, commonly banded or layered. The major problem with burning of bituminous coal is air pollution. A relatively soft coal containing the tarlike substance asphaltic bitumen. Its carbon content is 60-80%, the rest composed of water, air, hydrogen, and sulfur. It is of higher quality than lignite coal but of poorer quality than anthracite. It was usually formed as a result of high pressure on lignite. It dark brown to black in color, commonly banded or layered. The major problem with burning of bituminous coal is air pollution.

black locust (wood)

Heavy, dark wood of the species Robinia pseudoacacia, native to the Appalachian mountain region of the United States, and introduced into Europe, Asia, North Africa, and New Zealand as an ornamental and shade tree. It is used for making wheels, posts, gates, outdoor trim, and formerly for shipbuilding.

black marble

Marble that is predominantly black in color.

black oak (wood)

Wood of the species Quercus velutina.

black slate

Slate that is predominantly black in color.

black walnut (wood)

Wood of the species Juglans nigra native to the eastern and mid-western sections of North America, having a strong, durable, dark brown heartwood that finishes to a high polish. The sapwood is a pale yellow. The texture is coarse, but uniform and the grain is usually straight. Variations in color and waviness in grain are usually valued for decorative work. Black walnut is used for paneling, interior trim, furniture, cabinetry, clocks, propellers, gunstocks, sewing machines, piano cases, plywood, veneer, and decorative items.

blackboard slate

Select, unfading, black slate of uniform color and thickness with all edges ground and accurately squared so that joints can be made tight, smooth, and on the same plane.

blue brick

A brick of high strength whose blue color results from firing in a kiln with a flame of low oxygen content.

blue slate

Slate that has components of speculite and graphite in proportions that cause a bluish black color.

blue-and-white (ceramic glaze)

Refers to the glaze of white porcelain that is decorated with blue under the glaze. Underglaze blue had been used in the Middle East from the 9th century; it was introduced to China in the Yuan dynasty (1279-1368). Particularly notable are the blue-and-white wares produced in China during the Ming (1368-1644) and Qing (1644-1911) dynasties. Underglaze blue was introduced to Europe from China in the 18th century.


A type of bluish-gray feldspathic sandstone that is dense, fine-grained and splits easily into thin smooth slabs; for this reason it is often used as flagstone.

board and batten

Siding in which joints between vertically placed boards are covered by narrow strips of wood.

boards (flat objects)

Thin, flat, rigid objects, of considerable length or breadth compared to thickness, most often of wood, paperboard, or composite fiber materials.

bole (clay)

Soft, unctuous clays of various colors, used as pigments and in the ground for gold leaf.

bonds (masonry technique)

Methods by which masonry units, such as bricks or stones, are interlocked or joined through adhesion of mortar to the bricks. Bonds may be identified and referenced by the pattern on the surface of the masonry. For the process focusing on facing patterns, often in reference to ancient patterns, use children of "masonry facing (process)," although meaning overlaps.

bone (material)

The rigid, calcareous material that is white in color and forms the skeleton of vertebrates; primarily composed of calcium hydroxyapatite with smaller amounts of calcium carbonate, calcium fluoride, magnesium phosphate, and ossein, a high molecular weight protein. Bones have a concentric structure with central lymphatic canals surrounded by a spongy lamellar region protected by a dense outer cortex. Bone has been carved and used since ancient times for many purposes, including fish-hooks, spear heads, needles, handles, and art objects. Bones were also burnt to produce bone black and boiled to produce bone glue. Bone can be distinguished from ivory by being generally whiter, more porous, and less dense.

bone white

White pigment made from calcium hydroxyapatite and calcium carbonate derived from bone ash. It was used in grounds for silver point drawings, in making ceramics, and as a polishing compound.

borosilicate glass

Silicate glass containing at least five percent boric oxide and used in heat-resistant glassware.

botanical gardens

Primarily outdoor areas where a variety of plants are grown and displayed for scientific, educational, or artistic purposes.

Botticino marble

An Italian marble which can either be dark cream, light cream with brown markings, or light brown with whitish patches.


Vessels having a neck and mouth considerably narrower than the body, used for packaging and containing liquid and dry preparations. For vessels having wider necks and mouths, use "jars."


The largest rock fragment recognized by sedimentologists, a boulder is a detached rock mass larger than a cobble, having a diameter greater than 256 mm (10 in.).


Mixture of mud, moss, and lime (often in the form of ground shells) used as infill between wall timbers, characteristic of French-influenced architecture of the southern United States, especially Louisiana.

boxes (containers)

Rigid, often rectangular containers usually with a lid or cover in which something nonliquid is kept or carried.

boxwood (wood)

Dense, pale yellow wood from trees of the genus Buxus. Although difficult to carve, the wood has excellent dimensional stability and is very wear resistant. The hard, fine-grain wood is often used for printing blocks, rulers, mallets, architects scales, slide rules, modeling tools, musical instruments, engravings, inlays, small decorative items, and game pieces.

braced frames

Wooden building frames that use diagonal bracing between full-height corner posts and the plates; generally found in construction with timbers heavy enough to be mortised.

braid (trimming)

A narrow trimming made by a variety of techniques such as tablet weaving or braiding. It comes in a variety of fibers and weights, but is heavier than ribbon and flatter than cord.

No description is available for this term.

brass (alloy)

Alloy of copper and zinc, usually with copper as the major alloying element and zinc up to 40% by weight.

Brazilian rosewood (wood)

Dense, reddish-brown wood with black streaks obtained from the species Dalbergia nigra, native to Brazil. Brazilian rosewood is extremely rare because the trees were overharvested in the early 20th century. It is prized as a decorative wood, formerly used in the manufacture of furniture, cabinetry, and knife-handles. It is not a true Jacaranda.


A coarse-grained dastic rock, composed of angular broken rock fragments held together by a mineral cement or a fine-grained matrix.

breche violette marble

A coarse breccia marble of sharply angular red, pink, and white fragments in a dull red-brown matrix.

brick (clay material)

Clay or clay products formed into a rectangular block and hardened by drying in the sun or firing in a kiln.

brick red (color)

Variable orange colors resembling the color of bricks, which are typically rectangular clay products used for building.

brickwork (works by material)

Designs or arrangements comprising fired brick, sometimes glazed or otherwise decorated, arranged using bricklaying, especially arrangements in patterns or images.

brilliant yellow (pigment)

An unstandardized pigment name used for various yellow pigments, including but not limited to Naples yellow, a mixture of cadmium yellow with either lead white or zinc white, and a synthetic disazo dye.


Fixed or movable devices, such as louvers, designed to block the direct entrance of sun rays into buildings.

bronze (metal)

Refers to a broad range of alloys of copper, specifically any non-ferrous alloy of copper, tin, and zinc or other trace metals. Bronze was made before 3,000 BCE -- possibly as early as 10,000 BCE, although its common use in tools and decorative items is dated only in later artifacts. The proportions of copper and tin vary widely, from 70 to 95 percent copper in surviving ancient artifacts. Because of the copper base, bronze may be very malleable and easy to work. By the Middle Ages in Europe, it was recognized that using the metals in certain proportions could yield specific properties. Some modern bronzes contain no tin at all, substituting other metals such as aluminum, manganese, and even zinc. Historically, the term was used interchangeably with "latten." U.S. standard bronze is composed of 90% copper, 7% tin and 3% zinc. Ancient bronze alloys sometimes contained up to 14% tin.

brown oak

Wood from an oak tree that has a rich dark brown color as a result of being infected by beefsteak fungi.

brownstone (material)

A brown or reddish-brown sandstone whose grains are generally coated with iron oxide.

buckeye (wood)

General term for wood of any species of horse chestnut native to North America.

buffer (material)

Any substance capable in solution of neutralizing both acids and bases and thereby maintaining the original acidity or basicity of the solution.


Any of various siliceous, open-textured types of limestone or sandstone; uses include for millstones and as building material.

building board

Multipurpose board used in construction, such as for insulation or structural purposes.

building brick (clay products)

Brick made from natural clay and having no special surface treatment.

building paper

Paper used for insulation, as in walls, roofs, and between floors.

building sand

Selected sand used for concrete, for mortar, for laying bricks, and for plastering.

building stone

Any stone used for building.

built-in furniture

Furniture built into the walls or overall structure of a building. This can include, chests, cabinets, corner cupboards, bookcases, beds, and seating.


Historically, refers to modest one-story houses, originally with thatched roofs, derived from examples in India; by extension, in British contexts, use for detached one-story houses; in American contexts use more specifically for one- to one-and-a-half-story houses generally characterized by low-pitched gable or hipped roofs, usually with widely projecting, often bracketed eaves, dormers, and conspicuous front porches; popular in the United States from the late 19th to the early 20th century.

burl (wood)

Areas of tree growth where the grain has grown in a deformed manner, such as in small knots from dormant buds, forming rounded outgrowths on a tree trunk or branch and wavy and circular patterns in timber and veneer.

burl veneer

Veneer made from tree excrescences that are typically in the form of flattened hemispheres. For example, one type of burl veneer is made from the stumps of walnut trees.


Coarse canvas made of jute, used mainly for sacks and wrapping.

burled walnut

General term for a log, piece of timber, or veneer made from areas of burls in any variety of walnut wood, that is, from areas containing overgrown knots or excrescences. Burled walnut was used as veneers on chests and high chests in the William and Mary and sometimes the Queen Anne style, made in the United States during the 18th century.

burnt sienna (pigment)

Sienna earth that has been exposed to a red heat, causing it to turn a darker, cooler, less orange-red tone.

butterfly roofs

Roofs sloping downward from eaves on either side to a central valley. Roofs sloping downward from eaves on either side to a central valley.

butternut (wood)

Soft, yellowish-gray wood with a coarse grain from the species Juglans cinerea, ranging in color from light chestnut brown with darker zones in the heartwood to pale yellow or white in the sapwood. It polishes well and has been used for carving, furniture, and interior millwork


Pierlike masonry elements built to strengthen or support walls or resist the lateral thrust of vaults.

Buxus (genus)

Genus containing around 70 species slow-growing evergreen shrubs and small trees in the family Buxaceae.

Buxus sempervirens (species)
No description is available for this term.