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Bergson, Henri

(Encyclopedia)Bergson, Henri äNrēˈ bĕrgsôNˈ [key], 1859–1941, French philosopher. He became a professor at the Collège de France in 1900, devoted some time to politics, and, after World War I, took an inte...

radar

(Encyclopedia)radar, system or technique for detecting the position, movement, and nature of a remote object by means of radio waves reflected from its surface. Although most radar units use microwave frequencies, ...

matter

(Encyclopedia)matter, anything that has mass and occupies space. Matter is sometimes called koinomatter (Gr. koinos=common) to distinguish it from antimatter, or matter composed of antiparticles. The atomic th...

motorcycle

(Encyclopedia)motorcycle, motor vehicle whose design is based on the bicycle. The German inventor Gottlieb Daimler is generally credited with building the first practical motorcycle in 1885. The motorcycle did not ...

niobium

(Encyclopedia)niobium nīōˈbēəm [key], metallic chemical element; symbol Nb; at. no. 41; at. wt. 92.90638; m.p. about 2,468℃; b.p. 4,742℃; sp. gr. 8.57 at 20℃; valence +2, +3, +4, or +5. Niobium is a rare...

anxiety

(Encyclopedia)anxiety, anticipatory tension or vague dread persisting in the absence of a specific threat. In contrast to fear, which is a realistic reaction to actual danger, anxiety is generally related to an unc...

larynx

(Encyclopedia)larynx lârˈĭngks [key], organ of voice in mammals. Commonly known as the voice box, the larynx is a tubular chamber about 2 in. (5 cm) high, consisting of walls of cartilage bound by ligaments and ...

Dick, Philip K.

(Encyclopedia)Dick, Philip K. (Philip Kindred Dick), 1928–82, American science-fiction writer, b. Chicago. Dick often wrote of the psychological states of individuals caught in altered realities where the everyda...

Clarke, Arthur C.

(Encyclopedia)Clarke, Arthur C. (Sir Arthur Charles Clarke), 1917–2008, British science fiction writer. During World War II he served as a radar instructor and aviator in the Royal Air Force. After the war he obt...

edema

(Encyclopedia)edema ĭdēˈmə [key], abnormal accumulation of fluid in the body tissues or in the body cavities causing swelling or distention of the affected parts. Edema of the ankles and lower legs (in ambulato...
 

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