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Lorentz contraction

(Encyclopedia)Lorentz contraction lôrˈĕnts [key], in physics, contraction or foreshortening of a moving body in the direction of its motion, proposed by H. A. Lorentz on theoretical grounds and based on an earli...

gear

(Encyclopedia)CE5 Types of gears gear, toothed wheel, cylinder, or cone that transmits motion from one part of a machine to another; it is one of the oldest means of transmitting motion. When the teeth of two g...

international relations

(Encyclopedia)international relations, study of the relations among states and other political and economic units in the international system. Particular areas of study within the field of international relations i...

fetal tissue implant

(Encyclopedia)fetal tissue implant or fetal cell therapy, implantation of tissue from a fetus into a patient. In experimental procedures, fetal brain tissue has been implanted in the brains of patients with Parkins...

Sirleaf, Ellen Johnson

(Encyclopedia)Sirleaf, Ellen Johnson sĭrlēfˈ [key], 1938–, Liberian economist and political leader. Educated in the United States (M.P.A. Harvard, 1971), she worked in the Liberian government (1964–67, 1977�...

Monotheletism

(Encyclopedia)Monotheletism or Monothelitism both: mənŏthˈə lĭtĭzˌəm [key] [Gr.,=one will], 7th-century opinion condemned as heretical by the Third Council of Constantinople in 680 (see Constantinople, Thir...

osmosis

(Encyclopedia)osmosis ŏzmōˈsĭs [key], transfer of a liquid solvent through a semipermeable membrane that does not allow dissolved solids (solutes) to pass. Osmosis refers only to transfer of solvent; transfer o...

gyroscope

(Encyclopedia)CE5 Three-frame gyroscope gyroscope jīˈrəskōpˌ [key], symmetrical mass, usually a wheel, mounted so that it can spin about an axis in any direction. When spinning, the gyroscope has special p...

progressivism

(Encyclopedia)progressivism, in U.S. history, a broadly based reform movement that reached its height early in the 20th cent. In the decades following the Civil War rapid industrialization transformed the United St...

Sherman, William Tecumseh

(Encyclopedia)Sherman, William Tecumseh, 1820–91, Union general in the American Civil War, b. Lancaster, Ohio. Sherman is said by many to be the greatest of the Civil War generals. Sherman was promoted to lie...