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Bengaluru

(Encyclopedia)Bengaluru băng-gəlôrˈ [key], city (2021 pop. 5,104,047; est. pop. metropolitan area 12,327,000), ...

(Encyclopedia)ray, extremely flat-bodied cartilaginous marine fish, related to the shark. The pectoral fins of most rays are developed into broad, flat, winglike appendages, attached all along the sides of the head...

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...

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...

Oakland

(Encyclopedia)Oakland, city (1990 pop. 372,242), seat of Alameda co., W Calif., on the eastern side of San Francisco Bay; inc. 1852. Together with San Francisco and San Jose, the city comprises the fourth largest m...

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 ...

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 ...

National Radio Astronomy Observatory

(Encyclopedia)National Radio Astronomy Observatory (NRAO), federal observatory for radio astronomy, founded in 1956 and operated under contract with the National Science Foundation by Associated Universities, Inc.,...

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...