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chrysoberyl

(Encyclopedia)chrysoberyl krĭsˈəbĕrˌĭl [key] [Gr.,=golden beryl], a beryllium aluminate used as a gem. It has a vitreous luster and is transparent to translucent. The more valuable cat's-eye is a variety of c...

winter cress

(Encyclopedia)winter cress or upland cress, species of Barbarea, herbs of the family Cruciferae (or Brassicaceae; mustard family). The pungent leaves of several species have been used for salads or garnishes, and t...

molecular modeling

(Encyclopedia)molecular modeling, the computer simulation, by various means, of chemical structures or processes. Special computer-graphics programs can display three-dimensional images of molecular structures and ...

litmus

(Encyclopedia)litmus, organic dye usually used in the laboratory as an indicator of acidity or alkalinity (see acids and bases). Naturally pink in color, it turns blue in alkali solutions and red in acids. Commonly...

deliquescence

(Encyclopedia)deliquescence dĕlˌəkwĕsˈəns [key], conversion of a solid substance into a liquid as a result of absorption of water vapor from the air. Since impurities in a solid lower its melting point, the a...

ammoniac

(Encyclopedia)ammoniac or gum ammoniac əmōˈnēăkˌ [key], yellowish substance with a sickening, bitter taste, obtained from the milky exudate of the injured stem of a plant (Dorema ammoniacum) found in Iran, In...

fluoridation

(Encyclopedia)fluoridation flo͝orˌĭdāˈshən [key], process of adding a fluoride to the water supply of a community to preserve the teeth of the inhabitants. Tooth enamel ordinarily contains small amounts of fl...

peyote

(Encyclopedia)peyote pāōˈtē [key], spineless cactus (Lophophora williamsii), ingested by indigenous people in Mexico and the United States to produce visions. The plant is native to the SW United States, partic...

thymus gland

(Encyclopedia)thymus gland thīˈməs [key], mass of glandular tissue located in the neck or chest of most vertebrate animals. In humans, the thymus is a soft, flattened, pinkish-gray organ located in the upper che...

methyl

(Encyclopedia)methyl mĕthˈəl [key], CH3, organic free radical or alkyl group derived from methane by the removal of one hydrogen atom. ...