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emanation, in philosophy

(Encyclopedia)emanation ĕmənāˈshən [key] [Lat.,=flowing from], cosmological concept that explains the creation of the world by a series of radiations, or emanations, originating in the godhead. It is character...

apatite

(Encyclopedia)apatite ăpˈətīt [key], mineral, a phosphate of calcium containing chlorine or fluorine, or both, that is transparent to opaque in shades of green, brown, yellow, white, red, and purple. Apatite is...

molybdenite

(Encyclopedia)molybdenite məlĭbˈdənīt, mō– [key], a mineral, molybdenum disulfide, MoS2, blue-gray in color, with a metallic luster and greasy feel. It occurs in crystals of the hexagonal system but more co...

harvestman

(Encyclopedia)harvestman, arachnid, often called daddy longlegs because of its eight long, slender legs. The harvestman has a rounded or oval body possessing glands that give off an acrid scent. Its food consists o...

Ochoa, Severo

(Encyclopedia)Ochoa, Severo sāvāˈrō ōchōˈä [key], 1905–93, American biochemist and educator, b. Spain, M.D. Univ. of Madrid, 1929. After teaching at the universities of Madrid, Heidelberg, and Oxford, he ...

deodorizer

(Encyclopedia)deodorizer or deodorant, substance used to absorb or eliminate offensive odors. Disinfectants such as hydrogen peroxide, chlorine, and chlorine compounds eliminate odors caused by microorganisms. Adso...

secretion

(Encyclopedia)secretion, in biology, substance elaborated by the living material of an animal or plant. Secretions in humans can be produced by a single cell or by a group of cells commonly called a gland. Some sec...

Raman effect

(Encyclopedia)Raman effect räˈmən [key], appearance of additional lines in the spectrum of monochromatic light that has been scattered by a transparent material medium. The effect was discovered by C. V. Raman i...

verdigris

(Encyclopedia)verdigris vûrˈdəgrēsˌ [key], one of three copper acetates: blue verdigris, Cu(CH3COO)2·CuO·6H2O; green verdigris, 2Cu(CH3COO)2·CuO·6H2O; or neutral verdigris, Cu(CH3COO)2·H2O; or a mixture o...

thistle

(Encyclopedia)thistle, popular name for many spiny and usually weedy plants, but especially applied to members of the family Asteraceae (aster family) that have spiny leaves and often showy heads of purple, rose, w...