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sublimation, in chemistry

(Encyclopedia)sublimation sŭblĭmāˈshən [key], change of a solid substance directly to a vapor without first passing through the liquid state. The term is also used to describe the reverse process of the gas ch...

blood test

(Encyclopedia)blood test, examination of blood routinely or as an aid in diagnosing a suspected disease. Tests may be performed on whole blood or on the plasma portion only. Blood typing identifies the proteins at ...

columbine, in botany

(Encyclopedia)columbine kŏlˈəmbīn [key], any plant of the genus Aquilegia, temperate-zone perennials of the family Ranunculaceae (buttercup family), popular both as wildflowers and as garden flowers. Columbines...

earth, in chemistry

(Encyclopedia)earth, in chemistry, metallic oxide not readily reducible by chemical means, e.g., alkaline earths, rare earths, and alumina. The name is also applied to certain absorbent clays, e.g., fuller's earth,...

Consumers' Union

(Encyclopedia)Consumers' Union, product testing and rating organization founded (1936) to provide consumers with information and counsel regarding major retail goods and services. Through its monthly Consumer Repor...

corona, in astronomy

(Encyclopedia)corona, luminous envelope surrounding the sun, outside the chromosphere. Its density is less than one billionth that of the earth's atmosphere. The corona is visible only at the time of totality durin...

Bernard, Claude

(Encyclopedia)Bernard, Claude klōd bĕrnärˈ [key], 1813–78, French physiologist. He turned from literature to medicine, working in Paris under Magendie and teaching at the Collège de France and at the Sorbonn...

phase, in astronomy

(Encyclopedia)CE5 Phases of the moon phase, in astronomy, the measure of how much of the illuminated surface of a planet or satellite can be seen from a point at a distance from that body; the term is most ofte...

tortoiseshell

(Encyclopedia)tortoiseshell, horny, translucent, mottled plates covering the carapace of the tropical hawksbill turtle. The plates, too thin for most purposes in their original form, are usually built up in layers ...

equestrianism

(Encyclopedia)equestrianism, art of riding and handling a horse. Horseback riding was practiced as far back as the Bronze Age and was thereafter adapted to commerce, industry, war, sport, and recreation. Diverse st...