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silicon

(Encyclopedia)silicon, nonmetallic chemical element; symbol Si; at. no. 14; interval in which at. wt. ranges 28.084–28.086; m.p. 1,410℃; b.p. 2,355℃; sp. gr. 2.33 at 25℃; valence usually +4. Silicon is the ...

colon cancer

(Encyclopedia)colon cancer, cancer of any part of the colon (often called the large intestine). Colon cancer is the second most common cancer diagnosed in the United States. Epidemiological evidence has shown that ...

eugenics

(Encyclopedia)eugenics yo͞ojĕnˈĭks [key], study of human genetics and of methods to improve the inherited characteristics, physical and mental, of the human race. Efforts to improve the human race through bette...

iodine

(Encyclopedia)iodine īˈədīn, –dĭn [key] [Gr.,=violet], nonmetallic chemical element; symbol I; at. no. 53; at. wt. 126.90447; m.p. 113.5℃; b.p. 184.35℃; sp. gr. 4.93 at 20℃; valence −1, +1, +3, +5, o...

antimony

(Encyclopedia)antimony ănˈtĭmōˌnē [key] [Lat. antimoneum], semimetallic chemical element; symbol Sb [Lat. stibium,=a mark]; at. no. 51; at. wt. 121.760; m.p. 630.74℃; b.p. 1,750℃; sp. gr. (metallic form) ...

Apache

(Encyclopedia)Apache əpăchˈē [key], Native North Americans of the Southwest composed of six culturally related groups. They speak a language that has various dialects and belongs to the Athabascan branch of the...

Anthony, Susan Brownell

(Encyclopedia)Anthony, Susan Brownell, 1820–1906, American reformer and leader of the woman-suffrage movement, b. Adams, Mass.; daughter of Daniel Anthony, Quaker abolitionist. From the age of 17, when she was a ...

guidance and counseling

(Encyclopedia)guidance and counseling, concept that institutions, especially schools, should promote the efficient and happy lives of individuals by helping them adjust to social realities. The disruption of commun...

Gallic Wars

(Encyclopedia)Gallic Wars gălˈĭk [key], campaigns in Gaul led by Julius Caesar in his two terms as proconsul of Cisalpine Gaul, Transalpine Gaul, and Illyricum (58 b.c.–51 b.c.). Caesar's first campaign was to...

taxation

(Encyclopedia)taxation, system used by governments to obtain money from people and organizations. The revenue collected is used by the government to support itself and to provide public services. Aside from being r...