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hyperinsulinism

(Encyclopedia)hyperinsulinism, presence in the system of an above-normal amount of insulin, the substance secreted by the pancreas and needed by the body to utilize sugar. An increased amount of insulin in the body...

soil

(Encyclopedia)soil, surface layer of the earth, composed of fine rock material disintegrated by geological processes; and humus, the organic remains of decomposed vegetation. In agriculture, soil is the medium that...

topaz

(Encyclopedia)topaz tōˈpăz [key], aluminum silicate mineral with either hydroxyl radicals or fluorine, Al2SiO4(F,OH)2, used as a gem. It is commonly colorless or some shade of pale yellow to wine-yellow; pale bl...

gypsum

(Encyclopedia)gypsum jĭpˈsəm [key], mineral composed of calcium sulfate (calcium, sulfur, and oxygen) with two molecules of water, CaSO4·2H2O. It is the most common sulfate mineral, occurring in many places in ...

pigment

(Encyclopedia)pigment, substance that imparts color to other materials. In paint, the pigment is a powdered substance which, when mixed in the liquid vehicle, imparts color to a painted surface. The pigments used i...

hardness

(Encyclopedia)hardness, property of matter commonly described as the resistance of a substance to being scratched by another substance. The degree of hardness is relative, different substances being compared with o...

ash, in chemistry

(Encyclopedia)ash, in chemistry, solid residue of combustion. The chemical composition of an ash depends on that of the substance burned. Wood ash contains metal carbonates (e.g., potassium carbonate) and oxides fo...

laxative

(Encyclopedia)laxative, drug or other substance used to stimulate the action of the intestines in eliminating waste from the body. The term laxative usually refers to a mild-acting substance; substances of increasi...

sediment

(Encyclopedia)sediment, mineral or organic particles that are deposited by the action of wind, water, or glacial ice. These sediments can eventually form sedimentary rocks (see rock). Sediments form sedimentary ...

serpentine

(Encyclopedia)serpentine sûrˈpəntēn, –tīn [key], hydrous silicate of magnesium. It occurs in crystalline form only as a pseudomorph having the form of some other mineral and is generally found in the form of...