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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cable (material)

Strong, thick, linear material made of several strands of iron wire that are twisted or braided. Distinguished from "rope," which is usually made from synthetic or organic fibers.

cabled yarn

Yarn produced by twisting together two or more strands of plied yarn; the final twist is opposite to that of the plied ends.

Caen stone

A fine-grained French oolitic limestone that is cream in color and easily carved.

calcareous sandstone

Homogenous sandstone with a cement or matrix of calcium carbonate which binds together the quartz particles of which sandstone is mainly composed. It splits almost equally well in both directions and is easily worked but disintegrates upon exposure. Pure calcareous sandstone is white or cream in color; colors are due to impurities: yellow and red colors are due to the presence of iron oxides; green from glauconite; and black from manganese dioxide.


White or colored wall paint consisting of whiting, glue, linseed oil, or water colors.

calcium hydroxide

Colorless crystal or soft, white, alkaline powder prepared by reacting calcium oxide (lime) with water in a process called slaking. It is used in paints, dehairing hide, medicines, and in conservation for superficial protective treatments thanks to its conversion into calcium carbonate.


Cemented deposits of calcium carbonate materials.


Cotton textile, heavier than muslin, plain, dyed, or with patterns printed in one or more colors. In the 18th and 19th centuries, the term referred to printed, colored or plain cloth from India; now it refers generally to cotton prints with small, stylized patterns.

cameras (photographic equipment)

Lightproof boxes fitted with a lens through the aperture of which the image of an object is recorded on light-sensitive material such as film, or transformed into electrical impulses for direct transmission or for video recording.

camphor (resin)

The white resin of the species Cinnamomum camphora, used for hardening nitrocellulose plastic. Camphor is also in pharmaceuticals, disinfectants, and explosives.

canopy trees

Trees which form an overhanging shade or shelter.

canvas (textile material)

Closely woven textile made in various weights, usually of flax, hemp, jute, or cotton, used especially for sails, tarpaulins, awnings, upholstery, bags, and as a support for oil painting.


A heavy, oily substance distilled from an anthracene-oil or creosote-oil fraction of coal tar, sometimes chlorinated or otherwise treated, and used as a wood preservative, disinfectant, or insecticide.


Element that forms the framework for all tissues of plants and animals. Chemical symbol C and atomic number 6. Carbon may appear in many forms, including diamond, graphite, charcoal, carbon black, and fullerene. High quantities of carbon occur in coal, coke, oil, gasoline, and natural gas. Proteins such as hair, meat, and silk contain carbon and other elements. More than six and a half million compounds of the element carbon exist, including sugar, starch, and paper.

carbon steel

Steel that does not have specified minimum content levels of alloying elements. The term can also refer to steel that does not have more than 0.40% copper or to steel that has maximum content levels of the following: manganese 1.65%, silicon 0.60%, and copper 0.60%.

carbon tetrachloride

Volatile, noninflammable compound of carbon and chlorine.

Carboniferous limestone

Limestone from the Carboniferous period from about 345 to 280 million years ago.


A translucent red or orange variety of chalcedony, containing iron impurities. It is often used for seals and signet rings.


Material woven by the yard to be made up into carpets.

Carrara marble

Refers to a type of marble quarried in the area around Carrara, in Tuscany, Italy. It is characterized by a fine, compact grain and varies in color from pure white to creamy white, sometimes with a bluish tinge; it is a saccharoidal rock that can appear translucent in the finer grades. It has been a favorite stone of sculptors from antiquity to the present, including Michelangelo Buonarotti. Luna marble was the name used in ancient Rome.

Carrara structural glass (TM)

A type of structural plate glass that is ground to true plane surfaces; used for storefronts, countertops, tiling, and paneling. It is made in many colors in thicknesses from 11/32 to 1 1/2 inches (0.86 to 3.81 cm) or laminated to give different color effects.

Carya (genus)

Genus containing around 18 species of deciduous timber and nut-producing trees native to eastern North America and eastern Asia. Fossil remains identifiable as belonging to the genus are found in western North America, Greenland, Iceland, and Europe. It has tough heavy wood, and drupes (mostly with a hard woody rind or husk) enclosing 'nuts,' the kernels of which in several species are edible.

cascades (water features)

Man-made stepped waterfalls, whether naturalistic or architectural in form. For similar natural or highly naturalistic features, use "waterfalls."

casement windows

Windows having a sash that opens on hinges attached to the upright side of the frame.

cast iron

An iron alloy containing about 2 to 4% carbon and 1 to 3% silicon, having a high compressive strength but low tensile strength. Cast iron is manufactured by melting scrap iron or pig iron in a cupola that is in contact with the coal fuel, then casting the molten iron into a mold. A large range of building and decorative items are made of cast iron by pouring the molten metal into sand molds and then machining. It is inexpensive and easy to make. It was made in China by at least the 3rd century BCE; the technique for its production did not reach Europe until medieval times.

cast stone

Concrete with a fine aggregate or mortar which is cast into blocks or small slabs using special molds so as to resemble natural building stone.

cast-in-place concrete

Concrete that is deposited in liquid form in the place where it is required to harden as part of a structure; for concrete that is cast and cured in other than its final location, use "precast concrete."

casting plaster

Type of plaster of Paris especially prepared to have the properties most desirable for casting and carving; it is very fine-grained, absorbent, brilliantly white, slow setting, and capable of taking fine detail.


Any substance that in small amounts increases the rate of a chemical reaction without being consumed itself.

cattail (material)

Material derived from the long flat leaves of tall reedlike marsh plants of the genus Typha, used in making mats and chair seats, and since they swell when wet, leaves are used for caulking cracks in barrels and boats.

catwalks (circulation elements)

Narrow fixed walkways providing access to an otherwise inaccessible area or to lighting units, such as used above an auditorium or stage.

cedar (wood)

Wood of any of the four species of ornamental and timber evergreen conifers of the genus Cedrus.


Overhead surfaces of interior spaces, sometimes constructed to mask building systems or structural elements.

cellars (storerooms)

Rooms, often wholly or mostly below ground level, used for storage of food and often other items; for similar areas serving utility purposes or as living spaces, use "basements."


Glossy transparent material made from regenerated cellulose, typically in the form of thin sheets, usually moisture-proofed and sometimes dyed; impervious to dry gases, grease, and bacteria, and used as packaging or wrapping for food and other merchandise, envelope windows, and bags for dialysis.

cellulose (complex carbohydrate)

A complex natural carbohydrate, or polysaccharide, composed of long, connected chains of glucose molecules, forming the primary component in the cell walls of plants. Pure cellulose is an odorless, tasteless white powder. Cellulose exists in three forms: alpha, beta and gamma. Cellulose is used to manufacture paper and textiles, and as a raw material in rayon, cellophane, cellulose acetate, and celluloid.

cement (construction material)

Any of several finely powdered inorganic materials that can be mixed with water then dried to form a solid, durable mass, such as plaster, lime, pozzolan cement, and portland cement. It is used in construction as an ingredient of mortar and concrete.

cement mortar

Mortar made with portland cement, sand, and water, and sometimes with lime to aid spreading.

ceramic (material)

Refers to any of various hard, brittle, heat-resistant and corrosion-resistant materials made by shaping and then firing a nonmetallic mineral, such as clay, at a high temperature.

ceramic glaze

Thin, opaque, vitreous coating that is applied to the surface of a ceramic body by painting, spraying, or dipping, in order to add color, texture, or water resistance to the object. The glaze is applied to the surface of a fired ceramic piece, and then the piece is refired at a temperature that vitrifies the glaze, but is lower than the original firing temperature. Ceramic glazes are usually mixtures of silicates, colorants, and flux.

ceramic tile

Fired clay in various shapes and thicknesses and with a variety of uses, as for surface covering, drainage, or construction. For flat, solid, and relatively thin durable material used primarily for surface covering, use "tile."

Ceratonia siliqua (species)

Species of tree native to the eastern Mediterranean region and cultivated elsewhere. It is highly drought resistant. The tree reaches about 15 m (50 feet) in height, has glossy evergreen leaves, and produces long leathery pods that contain up to 15 hard brown seeds embedded in a sweet, edible pulp. The ripened pods are food for animals and also ground for a variety of uses by humans. The seeds are ground to produce a gum. The seeds were a standard of weight measurement in the ancient world, from which the concept "carat" is derived. The common names referring to locusts or St. John's bread come from the belief that the so-called "locusts" on which John the Baptist fed in the Biblical story were carob pods, not grasshoppers. There are various other references to the tree in the Bible.

chain link fences

Fences made of heavy steel wire which is interwoven in such a way as to provide a continuous mesh without ties or knots, except at the ends.

chains (object genres)

Series of objects connected one after the other, usually rings passing through one another.


A fine-grained limestone, or soft, earthy form of calcium carbonate; used chiefly in putty, crayons, paint, rubber products, linoleum, and as a pigment and abrasive.

chandeliers (hanging lights)

Lighting devices designed to hang from the roof or ceiling having two or more branches, holding candles, burners, or lamps; often ornamental.

charcoal (material)

A black, porous carbonaceous material comprising the carbon-containing residue from burned wood (e.g., willow, maple, beech, linden or plum) or other organic containing materials such as bone, plants or animals. It is used as a drawing material, for filtering liquids or air, and for other purposes.

cherry (wood)

General term referring to wood of several species of the genus Prunus native to Asia, Europe, and North America. The close, even-grain wood is strong and smells like roses when freshly cut. It is brownish to light red in color but darkens on exposure. Cherry wood takes a high polish and is valued for instrument cases, furniture, veneers, cabinetry, turnery, and decorative items. It was formerly used for airplane propellers.


Fine-grained, dense sedimentary rock consisting of interlocking crystals of quartz approximately 30 microns in diameter. Chert and its varieties, such as flint, are non-gem varieties of cryptocrystalline-granular quartz. These stones chip very easily and thus may be fashioned into tools with a sharp edge; they are also used for building.

chestnut (wood)

Wood of the genus Castanea; several species produce a light reddish brown wood that is relatively weak with a coarse grain. It is a soft light wood that splits easily but does not turn well. It is used for general construction, framing, fencing, poles, barrels, and veneer. Chestnut wood was commonly used for painted panels, especially in Italy.

chestnut oak (wood)

Refers specifically to the wood of the species Quercus prinus (also called Q. montana), used in making furniture. The term "chestnut oak" is also used informally as a general term referring to any of several species of oaks having leaves similar to chestnut trees.

chewing tobacco

Tobacco prepared for chewing, produced in a variety of forms such as compressed cakes, braided ropes, shredded leaves, and loose leaf ends, and usually flavored with substances such as licorice, spices, honey, or rum.

chicken wire

A light-gauge galvanized wire fencing, usually made with hexagonal mesh. So-called because it was originally used for enclosures for chickens.

chimney stacks

Chimneys containing a number of flues, especially when rising as shafts above a roof.

chimneys (architectural elements)

Vertical noncombustible structures containing flues for drawing off into the outside air products of combustion from, for example, stoves, fireplaces, and furnaces.

Chinese red

An unstandardized name for many red pigments, included but not limited to a variety of chrome reds, cinnabar, red mercuric sulfide, and vermilion.


Material, usuallly chips or sticks of wood, used for filling holes or cracks.


Textile, usually cotton or linen, dyed in a number of colors and usually glazed.

chrome steel

Any steel with chromium as the predominating element, the chromium making the steel hard and wear-resistant.

chrome yellow (pigment)

Pigment containing lead chromate, sometimes mixed with lead sulfate, ranging in color from lemon yellow to orange depending on its particle size, hydration state, and the percent lead chromate. It is is used in industrial paints, some artist's paints, and ceramic glazes.


Pure metallic element having symbol Cr and atomic number 24; an extremely hard, silvery white metal with a bluish tinge. Use also for the metal as processed and formed, usually in combination with other substances, to make various objects and materials, notably stainless steel, heat-resistant alloy, high-strength alloy steel, and for wear-resistant electroplating.


The incombustible residue of something burnt.

cinder blocks

Masonry units comprising lightweight cinder concrete, often used for interior partitions.

cinder concrete

A lightweight concrete made with cinder as the coarse aggregate.

cladding (metal coating)

Coating one metal with another by means of bonding, as to protect the inner metal from corrosion or for minting coins.

clapboard siding

Building siding constructed from a type of board bevelled toward one edge. Clapboards are attached overlapping each other horizontally, they are thinner at one edge, each board being made to overlap that below it.

classic cypress (wood)

Wood of the Cupressus sempervirens tree.


Naturally occurring sediments that are produced by chemical actions resulting during the weathering of rocks. It is often the term applied to all earths that form a paste with water and harden when heated.

clay mortar

Finely ground clay used as a plasticizer for masonry mortar.


Partially fused product from a kiln, which is ground and used for cement.

clinker brick

Very hard-burnt brick whose shape is distorted, owing to nearly complete vitrification; used for paving.


Generally, textile that is woven, felted, knit, pounded, or otherwise made into a flat piece. For textile in the form of continuous strands made from filaments of fiber by reeling, spinning, twisting, or throwing, see "yarn."

Coade stone

Building material, composed of ceramic similar to stoneware, developed in England around 1769, used primarily for architectural decoration.


Carbon-rich material that most often occurs in stratified sedimentary deposits. It is one of the most important of the primary fossil fuels. It is characterized by being solid, hard, opaque, black, or blackish, found in seams or strata in the earth, and largely used as fuel; it consists of carbonized vegetable matter deposited in former epochs of the world's history.

coal tar

Black viscous liquid with a naphthalene odor obtained by the distillation of bituminous coal. It can be separated into several fractions: gasoline, oil, creosote, and pitch. Coal tar is used in the manufacture of plastics, aniline dyes, for waterproofing, paints, roofing, roads, and as a pesticide.

coast Douglas fir (wood)

Wood from the species Pseudotsuga menziesii.

coast redwood (wood)

Wood from the Sequoia sempervirens, found along the California coast.

coating (material)

Use generally for any substance spread over a surface, usually for protection or decoration.

cob (clay mixture material)

Building material comprising a mixture of straw, gravel, and unburnt clay, especially used in the construction of walls, known as cob walls.

cobalt blue (pigment)

A bright, clear, blue pigment made by combining cobalt and aluminum oxides with phosphoric acid. It was discovered by Baron L. J. Thénard in France in 1802 and introduced to artists about 20 years later.


A rock fragment, rounded or otherwise abraded, with a diameter between 64 and 256 mm, being larger than a pebble and smaller than a boulder. The term can also refer more specifically to a rounded stone suitable for use in paving or other construction.

Cockeysville marble

A fine grained, magnesium-rich white marble from Cockeysville, Maryland; it has a few pale streaks or bands which give an effect of pale gray. One of the most popular types of marble used in nineteenth-century buildings in Washington, D.C., it comprised the top two thirds of the Washington Monument as well as the monolithic columns of the Capitol building extensions.

coconut (fruit)

Hard ovoid-shaped drupe (stone fruit) of the coconut palm (Cocos nucifera) native to the tropics. Coconuts have a fibrous outer husk and a woody inner shell that contains the coconut meat and white juice. Coconut shells range in diameter from 8 to 14 inches. Despite its name, the coconut is not classified as a nut.

common bond (masonry technique)

Technique of pattern bond in which a course of full-length headers occurs at regular intervals, usually every five or six courses; other courses are composed only of stretchers.

common hackberry (wood)

Wood of the species Celtis occidentalis; the wood is light-colored, yellowish gray to light brown with yellow streaks.

composite material

Material formed, either intentionally or through natural processes, from more than one constituent material, each with separate physical or chemical makeup.

composition (material)

Refers to various aggregate materials formed artificially from two or more substances, such as whiting, resin, and size used for modeling ornament in the late 18th century, or plaster of Paris, sawdust, bran, and glue used for dollmaking, or plastic cement-based mortars used in construction.

compressed wood

Wood which has been impregnated with resin and subjected to a high pressure to increase its density and strength.


A hard, strong construction material comprising a mixture of sand, gravel, crushed rock, or other aggregate, held together, typically by a hardened paste of cement and/or lime. Several types of aggregate are used such as crushed stone, slag, cinders or gravel. Ancient Romans developed pozzolan cement about the 3rd century BCE. Modern concretes use various cements such as portland or hydraulic. Concrete is durable and relatively inexpensive, used for foundations, bridges, dams, walls, and highways. Concrete is strong in compression but weak in tension so it is often reinforced with steel bars or wire netting. Once a concrete mixture is stirred with water and poured into a mold, it is allowed to cure slowly over about a week. Stresses, such as vibration, freezing, and rapid drying, will diminish the strength and durability of the concrete. As it ages, concrete is subject to erosion, spalling, and pollution. Poor mixing can cause erosion. Spalling can be due to freeze-thaw cycles of moisture and ice, salt crystallization, or corrosion of steel reinforcements. Acid rain can deplete the natural alkaline reserve of fresh concrete.

Concrete art

Term coined in 1930 by Theo van Doesburg to characterize a form of non-figurative painting in which the pictorial elements, planes and colors, have no significance other than themselves. He meant to distinguish between other forms of abstraction, indebted to illusionism mimicing the visible or natural world, and paintings that are products of the human mind. The definition was elaborated upon by Max Bill in 1936 in a catalog for the exhibition Zeitprobleme in der Schweizer Malerei und Plastik. In 1960 Bill organized an exhibition of work that fit his definition, and that established Concrete art as an international movement.

concrete blocks

Large units of building material made from a mixture of cement and an aggregate, usually 8 x 16 inches and of various thicknesses. A mixture of cement, aggregate, and water is vibrated and compacted in steel molds and then cured in air, steam, or under autoclaving processes. Became a very popular building material beginning in the early 20th century.

concrete brick
No description is available for this term.

concrete masonry units

Units for masonry construction made primarily of concrete; the most common types are concrete bricks and concrete blocks.

concrete pavers

Concrete mixers, usually mounted on crawler tracks, that mix and place concrete pavement on the subgrade.

concrete slabs

Flat plates made of concrete and used as structural elements in architecture.

cone shell

The shell of various marine snails of the genus Conus and family Conidae, typically straight-sided with tapering body whorl, low spire, and narrow opening, and of vivid colors and eccentric markings; it is valued as a material for bracelets, disks, and other ornament.

No description is available for this term.

copper (metal)

Pure metallic element having the symbol Cu and atomic number 29; a reddish brown, ductile metal that is present in the earth's crust, occurring as a native metal and as ores of sulfide, sulfate and carbonate (azurite, malachite, etc.). It was the first metal used by humans, probably from about 8000 BCE, in the regions of Mesopotamia and India. By about 3800 BCE copper was made into bronze for weapons and knives. Today, copper is one of the most widely used metals because it has high electrical and thermal conductivity, can be easily fabricated, is ductile and polishes well. In moist air, copper forms a protective green film of basic carbonate. Metallic copper combines well with other metals to form alloys, most commonly brass and bronze. Copper and its alloys are used for wire, electrical devices, pipes, cooking vessels, ammunition, ornamental trim, roofing, grillwork, coins, musical instruments, jewelry, and sculptures.

copper alloy

Alloy in which copper is the principle element.

copper green (pigment)

A pale blue green pigment made from copper salts.