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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laburnum (wood)

Wood of the trees of the genus Laburnum, having a striking, dark greenish brown or reddish brown color, fine grain, and capable of taking a high polish. It is typically used for cabinetmaking and inlay.

lac (resin)

A resinous substance excreted by the lac insect, especially those who live on the twigs and soft new branches of several varieties of soapberry and acacia trees. Lac is used in the manufacture of varnishes (shellac), sealing wax (lac wax), and red colorants (lac dye) as early as ca. 1200 BCE in India. The word "lac" is the English version of Persian and Hindi words meaning "hundred thousand," indicating the large number of the tiny insects required to produce lac.

lacquer (material)

Paint, varnish, or another material applied by coating, made of the resinous exudation of certain trees or from insects, and that dries with a high gloss or matte finish. In most lacquers resin is dissolved in a volatile solvent or a drying oil and hardens by evaporation. Lacquer may be applied in many layers, so the thick surface may be set with inlays or carved.

lagoons (bodies of water)

Bodies of shallow water separated from the sea by a barrier, such as a sandbar or coral reef.


Flexible material made by bonding together two or more layers of materials with adhesive. For resin-impregnated laminate, such as paper or fabric, use "plastic laminate." For thin sheets of layered plastic, use "laminated plastic."

laminated veneer lumber

Lumber produced by overlaying and adhering multiple layers of thin wood. This composite wood product is stronger and more uniform than conventional milled lumber and less likely to warp or shrink.

lantern lights

Raised skylights or small lanterns with the sides mostly glazed, erected on a roof to admit light to the space below.

lapis lazuli (rock)

A granular crystalline rock composed essentially of lazurite and calcite. This is an old name for gem-variety lazurite.

larch (wood)

Wood of the genus Larix, native to cool and sub-Arctic parts of the Northern Hemisphere. Most larch timber is coarse-grained, hard, and heavy, and is used for the construction of telephone poles, mine timbers, and railroad ties.

lath (grounding surface)

The surface, other than masonry, to which plaster is applied; made from various materials, including expanded metal mesh, gypsum board, or other material that will sufficiently bond the plaster.

laths (wood by form)

Thin, narrow, flat pieces of wood used for many purposes, such as in constructing lattices of trellis work, Venetian blinds, or to form a groundwork upon which to fasten the slates or tiles of a roof or the plaster of a wall or ceiling. For groundwork of any material upon which plaster or another such material is applied, use "lath (grounding surface)."


Secondary roof support members, usually light poles or trimmed saplings, placed perpendicularly or in a herringbone pattern over vigas (primary beams) in Native American or Spanish American adobe construction.

lauan (wood)

Wood obtained from any of several species of the genus Shorea; sold as Philippine mahogany on the American market. It is a reddish- brown wood resembling mahogany in texture, weight, and strength, but it is not dimensionally stable with changes in relative humidity. Lauan wood is used for furniture, cabinetry, veneers, and boat building.

laurel (wood)

Wood of trees belonging to the genus Laurus, native to India, West Pakistan and Burma. It is used extensively for making furniture, cabinet-making, interior joinery, and staircases.

Laurus nobilis (species)

Species of aromatic evergreen tree native to the Mediterranean region but widely cultivated elsewhere, growing 6-18 meters (20-60 feet) in height and having stiff, alternate, oval leaves that are dull and leathery, around 8 cm (3.5 inches) long; the leaf edges are smooth and often wavy, used as a cooking herb. In ancient Greece the wreath of honor placed upon the heads of heroes and winners of games was made from the leaves and branches of this species. The small and inconspicuous flowers are yellowish or greenish white. The fruit is a green, purple, or blackish berry containing a single seed, and when pressed, producing an aromatic oil. The wood is strong and elastic, used for carving and marquetry.


Molten volcanic rock that issues from a volcano or fissure in the earth's surface; also, the same material after being cooled and solidified.

lava rock masonry
No description is available for this term.

lawn (textile)

Sheer, lightweight plain-woven textile, originally of linen now also of fine combed cotton yarn, filled with starch or sizing. often used for handkerchiefs, aprons, and curtains.

lawns (landscaped grass)

Areas of cultivated grass or other ground cover maintained for aesthetic quality or recreation.

lead (metal)

Pure metallic element having symbol Pb and atomic number 82; soft, dense ductile metal of a dull gray color, shiny when freshly cut, occuring naturally most often as a sulfide in the mineral galena. Other lead minerals include anglesite (lead sulfate) and cerussite (lead carbonate). Native metallic lead was found and used from about 3600-2600 BCE when the technique for obtaining lead from roasting the sulfide ore (galena) was discovered. Lead was used to make small cast items such as coins and statuettes, plumbing pipes, spires, statues, cisterns, gargoyles, pigments (lead white, litharge, orange mineral, etc.), as a component in pottery glazes, for roofing, flashing, stained glass windows, as a soft solder, and as radiation shielding.

lead glass

Glass containing a high proportion of lead oxide and having a relatively high refractive index, with poor acid resistance and low rigidity; used in many optical components, neon-sign tubing, and light bulbs.


Visual works or parts of works made from lead, particularly sculptural, ornamental, or architectural objects. Usage may include plumbing or glazier's work.


The skin or hide of an animal that has been tanned to render it resistant to putrefication and relatively soft and flexible when dry. For composite material made from scrap leather pieces, use "maril."

LED bulbs

Lighting devices that incorporate an array of LEDs within a bulb-shaped enclosure, usually made of glass. These are used for general lighting applications, in most cases as a replacement for incandescent light sources, as they offer more efficient energy performance.


A soft coal, usually dark brown, often having a distinct woodlike texture, and intermediate in density and carbon content between peat and bituminous coal.

lime (fruit)

General term for a number of different citrus fruits, both established species and hybrids, that are typically round, green to yellowish green in color, containing acidic pulp that is sweeter than lemons, and of a size usually smaller than lemons.

lime concrete

A concrete made from a mixture of lime, sand, and gravel, widely used before the lime matrix was replaced by portland cement.

lime mortar

A mixture of hydrated lime, sand, and water, which has a compressive strength up to 400 psi.

lime plaster

A type of plaster composed of calcium oxide (lime). Lime plaster has been used since antiquity, prepared by heating limestone to remove carbon dioxide and convert it to anhydrous calcium oxide (quicklime). When quicklime is mixed with water, it converts to calcium hydroxide (slaked lime).


General name for a sedimentary rock existing in many varieties, consisting primarily of calcite or dolomite.


Limonite refers to any hydrated iron ore. A brownish yellow deposit, it is formed by precipitation in marshy areas and is found mixed in clay and sand as loose powder or as a mass. Limonite is also called bog iron ore.

linen (material)

General name for textile woven from the spun fiber of the flax plant.


Durable floor coverings made primarily of linseed oil, with a filler of cork dust or wood flour, and flax, with pigments added to create the desired colors and patterns; also, similar floor coverings made with substitutes for the linseed oil or filler or both.

linter (fiber)

The short downy hairs or fuzz adhering to the cotton seeds (removed by a machine called a linter), which is unsuitable for spinning into yarn and is used as a source of celluloseu. Linter is useful in papermaking and upholstery.

Liriodendron tulipifera (species)

Species of large, columnar tree native to North America, the common name referring to the large flowers that superficially resemble tulips, although the plants are instead closely related to magnolias. They provide food and shelter to butterflies and other animals. They are used for fine-grained, stable timber and landscaping.

live oak (wood)

General term for wood of any species of evergreen oak native to the U.S., often either Quercus virginiana or Q. agrifolia. The light brown wood of live oak trees is strong and hard, once highly valued by shipbuilders. Now the trees are mainly grown as shade trees.

living rock

Refers to rock in its original environment, as opposed to having been quarried. It typically refers to rock that is carved or otherwise used in situ, often to sculpture or architecture carved in situ.

lodgepole pine (wood)

Wood from the Pinus contorta, found in western North America.

log (wood)

The unhewn portion of a felled tree, including a length cut off for use as firewood, construction, or another purpose.

log construction

Vernacular form of construction using entire logs. One of the oldest known methods of construction, log construction has been used for dwellings, as well as churches and bridges. Log walls are produced by stacking logs and filled with mud or other insulating materials. Structures made of logs are characterized by corner joints that interlock with a cross-lap connection, or with dovetailing.

logwood (colorant)

A blackish blue or blood red natural colorant extracted from the logwood tree, Haematoxylon campechianum, of Central America, Mexico, and the West Indies. It was formerly used to make black ink, and is still used to dye textiles black.

longleaf pine (wood)

Wood from the Pinus palustris, found in the southern United States and valued as timber.


Material cut from timber to sizes and forms suitable for structural use.

luster (textile)

Textile made with cotton, silk, or linen warp and wool, mohair, alpaca, or some other glossy hair fiber as weft in order to produce a lustrous surface.