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bedbug

(Encyclopedia)bedbug, any of the small, blood-sucking bugs of the family Cimicidae, which includes about 30 species distributed throughout the world. Bedbugs are flat-bodied, oval, reddish brown, and about 1⁄4 in...

thyroxine

(Encyclopedia)thyroxine thīrŏkˈsēn [key], substance secreted by the thyroid gland. The hormone thyroxine forms by combining the amino acid tyrosine with iodine. Complexed to a protein, it is stored in the folli...

World Health Organization

(Encyclopedia)World Health Organization (WHO), specialized agency of the United Nations, established in 1948, with its headquarters at Geneva. WHO admits all sovereign states (including those not belonging to the U...

synchrotron radiation

(Encyclopedia)synchrotron radiation, in physics, electromagnetic radiation emitted by high-speed electrons spiraling along the lines of force of a magnetic field (see magnetism). Depending on the electron's energy ...

stethoscope

(Encyclopedia)stethoscope stĕthˈəskōpˌ [key] [Gr.,=chest viewer], instrument that enables the physican to hear the sounds made by the heart, the lungs, and various other organs. The earliest stethoscope, devis...

Bill and Melinda Gates Foundation

(Encyclopedia)Bill and Melinda Gates Foundation, philanthropic institution founded in 1994 by Microsoft chairman Bill Gates and his wife, Melinda, to improve the lives of the poor throughout the world, primarily th...

dentistry

(Encyclopedia)dentistry, treatment and care of the teeth and associated oral structures. Dentistry is mainly concerned with tooth decay, disease of the supporting structures, such as the gums, and faulty positionin...

swine

(Encyclopedia)swine, name for any of the cloven-hoofed mammals of the family Suidae, native to the Old World. A swine has a rather long, mobile snout, a heavy, relatively short-legged body, a thick, bristly hide, a...

prostitution

(Encyclopedia)prostitution, act of granting sexual access for payment. Although most commonly conducted by females for males, it may be performed by females or males for either females or males. Prostitution in A...

Linnaeus, Carolus

(Encyclopedia)Linnaeus, Carolus kärōˈləs lĭnāˈəs [key], 1707–78, Swedish botanist and taxonomist, considered the founder of the binomial system of nomenclature and the originator of modern scientific clas...

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