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feldspar

(Encyclopedia)feldspar fĕlˈspär [key], an abundant group of rock-forming minerals which constitute 60% of the earth's crust. Chemically the feldspars are silicates of aluminum, containing sodium, potassium, iron...

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...

AZT

(Encyclopedia)AZT or zidovudine zīdōˈvyo͞odēnˌ [key], drug used to treat patients infected with the human immunodeficiency virus (HIV), which causes AIDS; also called azidothymidine. Originally developed in 1...

baboon

(Encyclopedia)baboon, any of the large, powerful, ground-living monkeys of the genus Papio, also called dog-faced monkeys. Five subspecies live in Africa, with one species extending into the Arabian peninsula. They...

food pyramid

(Encyclopedia)CE5 The U.S. Department of Agriculture used (1992–2005) this pyramid to show the basis of a healthy diet, dividing foods into five nutritional groups and recommending the number of daily average ...

Eckhart, Meister

(Encyclopedia)Eckhart, Meister mīsˈtər ĕkˈhärt [key] (Johannes Eckhardt), c.1260–c.1328, German mystical theologian, b. Hochheim, near Gotha. He studied and taught in the chief Dominican schools, notably at...

sundial

(Encyclopedia)sundial, instrument that indicates the time of day by the shadow, cast on a surface marked to show hours or fractions of hours, of an object on which the sun's rays fall. Although any object whose sha...

Zaragoza

(Encyclopedia)Zaragoza sârˌəgōˈsə [key], city (1990 pop. 592,686), capital of Zaragoza prov. and leading city of Aragón, NE Spain, on the Ebro River. An important commercial and communications center, it is ...

Weyden, Roger van der

(Encyclopedia)Weyden, Roger van der vän dər vīˈdən [key], c.1400–1464, major early Flemish master, known also as Roger de la Pasture. He is believed to have studied with Robert Campin. His early works also s...

Biedermeier

(Encyclopedia)Biedermeier bēˈdərmīər [key], name applied, at first in a joking spirit, to a period of European culture and a style of furniture, decoration, and art originating in Germany early in the 19th cen...