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Tharp, Twyla

(Encyclopedia)Tharp, Twyla twīˈlə [key], 1941–, American dancer and choreographer, b. Portland, Ind. An eclectic, innovative choreographer and dancer, she danced (1963–65) with Paul Taylor. For more than 20 ...

thermoelectricity

(Encyclopedia)thermoelectricity, direct conversion of heat into electric energy, or vice versa. The term is generally restricted to the irreversible conversion of electricity into heat described by the English phys...

thymine

(Encyclopedia)thymine thīˈmēn [key], organic base of the pyrimidine family. Thymine was the first pyrimidine to be purified from a natural source, having been isolated from calf thymus and beef spleen in 1893–...

toxic waste

(Encyclopedia)toxic waste is waste material, often in chemical form, that can cause death or injury to living creatures. It usually is the product of industry or commerce, but comes also from residential use, agric...

chain

(Encyclopedia)chain, flexible series of connected links used in various ways, especially for the transmission of motive power, for hoisting (see pulley), and for securing or fastening. Commonly, mechanical energy f...

Five-Year Plan

(Encyclopedia)Five-Year Plan, Soviet economic practice of planning to augment agricultural and industrial output by designated quotas for a limited period of usually five years. Nations other than the former USSR a...

uracil

(Encyclopedia)uracil yo͝orˈəsĭl [key], organic base of the pyrimidine family. It was isolated from herring sperm and also produced in a laboratory in 1900–1901. When combined with the sugar ribose in a glycos...

urinalysis

(Encyclopedia)urinalysis yo͝orˌənălˈĭsĭs [key], clinical examination of urine for the purpose of medical diagnosis. Urine is initially examined for such characteristics as color, odor, and specific gravity. ...

polonium

(Encyclopedia)polonium pəlōˈnēəm [key], radioactive chemical element; symbol Po; at. no. 84; mass no. of most stable isotope 209; m.p. 254℃; b.p. 962℃; sp. gr. about 9.4; valence +2 or +4. Polonium is an e...

hummingbird

(Encyclopedia)hummingbird, common name for members of the family Trochilidae, small, strictly New World birds, related to the swifts, and found chiefly in the mountains of South America. Hummingbirds vary in size f...