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epilepsy

(Encyclopedia)epilepsy, a chronic disorder of cerebral function characterized by periodic convulsive seizures. There are many conditions that have epileptic seizures. Sudden discharge of excess electrical activity,...

zirconium

(Encyclopedia)zirconium zərkōˈnēəm [key], metallic chemical element; symbol Zr; at. no. 40; at. wt. 91.224; m.p. about 1,852℃; b.p. 4,377℃; sp. gr. 6.5 at 20℃; valence +2, +3, or +4. Zirconium is a very ...

nickel

(Encyclopedia)nickel, metallic chemical element; symbol Ni; at. no. 28; at. wt. 58.6934; m.p. about 1,453℃; b.p. about 2,732℃; sp. gr. 8.902 at 25℃; valence 0, +1, +2, +3, or +4. Nickel is a hard, malleable, ...

paper

(Encyclopedia)paper, thin, flat sheet or tissue made usually from plant fiber but also from rags and other fibrous materials. It is used principally for printing and writing on but has many other applications. The ...

gambling

(Encyclopedia)gambling or gaming, betting of money or valuables on, and often participation in, games of chance (some involving degrees of skill). In England and in the United States, gambling was not a common-law ...

transistor

(Encyclopedia)CE5 Simple transistor circuit transistor, three-terminal, solid-state electronic device used for amplification and switching. It is the solid-state analog to the triode electron tube; the transist...

tire

(Encyclopedia)tire, device made of rubber and fabric and attached to the outer rim of a vehicle wheel. Solid rubber tires were in limited use before 1850; they are still used in some special applications, e.g., for...

balance

(Encyclopedia)balance, instrument used in laboratories and pharmacies to measure the mass or weight of a body. A balance functions by measuring the force of gravity that the earth exerts on an object, i.e., its wei...

bee

(Encyclopedia)bee, name for flying insects of the superfamily Apoidea, in the same order as the ants and the wasps. Bees are characterized by their enlarged hind feet, typically equipped with pollen baskets of stif...

news agency

(Encyclopedia)news agency, local, national, international, or technical organization that gathers and distributes news, usually for newspapers, periodicals, and broadcasters. From 1915 until the 1940s, news age...

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