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sewing machine

(Encyclopedia)sewing machine, device that stitches cloth and other materials. An attempt at mechanical sewing was made in England (1790) with a machine having a forked, automatic needle that made a single-thread ch...

compressor

(Encyclopedia)compressor, machine that decreases the volume of air or other gas by the application of pressure. Compressor types range from the simple hand pump and the piston-equipped compressor used to inflate ti...

estrogen

(Encyclopedia)CE5 estrogen ĕsˈtrəjən [key], any one of a group of hormones synthesized by the reproductive organs and adrenal glands in females and, in lesser quantities, in males. The estrogens cause the th...

psychotherapy

(Encyclopedia)psychotherapy, treatment of mental and emotional disorders using psychological methods. Psychotherapy, thus, does not include physiological interventions, such as drug therapy or electroconvulsive the...

Fourteen Points

(Encyclopedia)Fourteen Points, formulation of a peace program, presented at the end of World War I by U.S. President Woodrow Wilson in an address before both houses of Congress on Jan. 8, 1918. The message, though ...

isotope

(Encyclopedia)CE5 Isotopes of hydrogen isotope īˈsətōp [key], in chemistry and physics, one of two or more atoms having the same atomic number but differing in atomic weight and mass number. The concept of ...

solar energy

(Encyclopedia)solar energy, any form of energy radiated by the sun, including light, radio waves, and X rays, although the term usually refers to the visible light of the sun. Solar energy is needed by green plants...

spintronics

(Encyclopedia)spintronics, spin electronics, or magnetoelectronics, science and technology that harnesses the spin state of electrons in addition to the electrical charge state to store data or perform calculation...

camel

(Encyclopedia)camel, ruminant mammal of the family Camelidae. The family consists of three genera, the true camels of Asia (genus Camelus); the wild guanaco and the domesticated alpaca and llama, all of South Ameri...

uranium

(Encyclopedia)uranium yo͞orāˈnēəm [key], radioactive metallic chemical element; symbol U; at. no. 92; mass number of most stable isotope 238; m.p. 1,132℃; b.p. 3,818℃; sp. gr. 19.1 at 25℃; valence +3, +4...