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osteoporosis

(Encyclopedia)osteoporosis ŏsˌtēōˌpərōˈsĭs [key], disorder in which the normal replenishment of old bone tissue is severely disrupted, resulting in weakened bones and increased risk of fracture; osteopenia...

ordeal

(Encyclopedia)ordeal, ancient legal custom whereby an accused person was required to perform a test, the outcome of which decided the person's guilt or innocence. By an ordeal, appeal was made to divine authority t...

Manhattan Project

(Encyclopedia)Manhattan Project, the wartime effort to design and build the first nuclear weapons (atomic bombs). With the discovery of fission in 1939, it became clear to scientists that certain radioactive materi...

Russell, John Russell, 1st Earl

(Encyclopedia)Russell, John Russell, 1st Earl, 1792–1878, British statesman; younger son of the 6th duke of Bedford, known most of his life as Lord John Russell. He became a Whig member of Parliament in 1813 and ...

blood groups

(Encyclopedia)blood groups, differentiation of blood by type, classified according to immunological (antigenic) properties, which are determined by specific substances on the surface of red blood cells. Blood group...

Sistine Chapel

(Encyclopedia)Sistine Chapel sĭsˈtēn [key] [for Sixtus IV], private chapel of the popes in Rome, one of the principal glories of the Vatican. Built (1473) under Pope Sixtus IV, it is famous for its decorations. ...

tuberculosis

(Encyclopedia)tuberculosis (TB), contagious, wasting disease caused by any of several mycobacteria. The most common form of the disease is tuberculosis of the lungs (pulmonary consumption, or phthisis), but the int...

electronic game

(Encyclopedia)electronic game, device or computer program that provides entertainment by challenging a person's eye-hand coordination or mental abilities. Made possible by the development of the microprocessor, ele...

Deep Sea Drilling Project

(Encyclopedia)Deep Sea Drilling Project, U.S. program designed to investigate the evolution of ocean basins by core drilling of ocean sediments and underlying oceanic crust. Funded by the National Science Foundatio...

cystic fibrosis

(Encyclopedia)cystic fibrosis sĭsˈtĭk fībrōˈsĭs [key], inherited disorder of the exocrine glands (see gland), affecting children and young people; median survival is 25 years in females and 30 years in males...