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pole, in electricity and magnetism

(Encyclopedia)pole, in electricity and magnetism, point where electric or magnetic force appears to be concentrated. A single electric charge located at a point is sometimes referred to as an electric monopole. An ...

Parkinson's disease

(Encyclopedia)Parkinson's disease or Parkinsonism, degenerative brain disorder first described by the English surgeon James Parkinson in 1817. When there is no known cause, the disease usually appears after age 40 ...

quelea

(Encyclopedia)quelea kwēˈlēə [key], common name for an East African weaverbird, Quelea quelea. Less than 5 in. (13 cm) long and weighing slightly more than 1⁄2 oz (1.4 grams), these tiny birds are found throu...

pardon

(Encyclopedia)pardon, in law, exemption from punishment for a criminal conviction granted by the grace of the executive of a government. A general pardon to a class of persons guilty of the same offense (e.g., insu...

West Nile virus

(Encyclopedia)West Nile virus, microorganism and the infection resulting from it, which typically produces no symptoms or a flulike condition. The virus is a flavivirus and is related to a number of viruses that ca...

Heleb

(Encyclopedia)Heleb hēˈlĕb [key], in the Bible, mighty man. An alternate form is Heled. He may be the captain Heldai in First Chronicles. ...

wen

(Encyclopedia)wen, benign, slow-growing, painless cyst of the skin resulting from obstruction of the sebaceous gland ducts. It is frequently found on the scalp, ears, face, back, or scrotum. Usually no treatment is...

guilt

(Encyclopedia)guilt, in psychology, a term denoting an unpleasant feeling associated with unfulfilled wishes. Sigmund Freud initially contended that sexual drives produce sense of guilt in the superego, the moral c...

epithelium

(Encyclopedia)epithelium ĕpˌəthēˈlēəm [key], sheet of tissue that covers or lines the external and internal body surfaces. The epithelium is closely packed, has little intercellular material, and is lacking ...

injection

(Encyclopedia)injection, introduction of a fluid into the body, usually by means of a needle and syringe. The material injected may be a test substance (as in determining allergic sensitivity or immunity to a disea...