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spring, in geology

(Encyclopedia)spring, in geology, natural flow of water from the ground or from rocks, representing an outlet for the water that has accumulated in permeable rock strata underground. Some of the water that falls as...

Wilczek, Frank Anthony

(Encyclopedia)Wilczek, Frank Anthony, 1951–, American physicist, b. New York City, Ph.D. Princeton, 1974. Wilczek was a professor at Princeton (1974–80, 1989–2000) and at the Univ. of California, Santa Barbar...

amphibian, in zoology

(Encyclopedia)amphibian, in zoology, cold-blooded vertebrate animal of the class Amphibia. There are three living orders of amphibians: the frogs and toads (order Anura, or Salientia), the salamanders and newts (or...

seal, in zoology

(Encyclopedia)seal, carnivorous aquatic mammal with front and hind feet modified as flippers, or fin-feet. The name seal is sometimes applied broadly to any of the fin-footed mammals, or pinnipeds, including the wa...

brake, in technology

(Encyclopedia)CE5 Shoe brake CE5 Disk brake brake, in technology, device to slow or stop the motion of a mechanism or vehicle. The vacuum brake system, or vacuum brake, depends upon the use of a vacuum to ...

calliope, in music

(Encyclopedia)calliope, in music, an instrument also called steam organ or steam piano in which steam is forced through a series of whistles controlled by a keyboard. It is usually played mechanically, and its shri...

mole, in chemistry

(Encyclopedia)mole, in chemistry, a quantity of particles of any type equal to Avogadro's number, or 6.02×1023 particles. One gram-molecular weight of any molecular substance contains exactly one mole of molecules...

competition, in biology

(Encyclopedia)competition, in biology, relationship between members of the same or different species in which individuals are adversely affected by those having the same living requirements, such as food or space. ...

style, in printing

(Encyclopedia)style, in printing, arbitrary rule or collection of rules governing the practice of a printer or a publisher in doubtful or disputed matters to obtain consistency. Correct spelling is a matter of lite...

Canopus, in astronomy

(Encyclopedia)Canopus, in astronomy, 2d brightest star in the sky, located in the constellation Carina, which is part of the ancient constellation Argo Navis; Bayer designation α Carinae; 1992 position R.A. 6h23.8...