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fertilizer

(Encyclopedia)fertilizer, organic or inorganic material containing one or more of the nutrients—mainly nitrogen, phosphorus, and potassium, and other essential elements required for plant growth. Added to the soi...

trypanosome

(Encyclopedia)trypanosome trĭpˈənəsōmˌ [key], microscopic, one-celled protozoan of the genus Trypanosoma, typically living as an active parasite in the bloodstream of a vertebrate; hundreds of species are kno...

Varanasi

(Encyclopedia)Varanasi bənäˈrĭz [key], city (1991 pop. 1,030,863), Uttar Pradesh state, N central India, on the Ganges River. Although a rail hub and trade center, Varanasi is chiefly important as a holy city. ...

Veblen, Thorstein

(Encyclopedia)Veblen, Thorstein thôrˈstīn vĕbˈlən [key], 1857–1929, American economist and social critic, b. Cato Township, Wis. Of Norwegian parentage, he spent his first 17 years in Norwegian-American far...

ovary

(Encyclopedia)ovary, ductless gland of the female in which the ova (female reproductive cells) are produced. In vertebrate animals the ovary also secretes the sex hormones estrogen and progesterone, which control t...

fruit fly

(Encyclopedia)fruit fly, common name for any of the flies of the families Tephritidae and Drosophilidae. All fruit flies are very small insects that lay their eggs in various plant tissues. The Tephritidae contains...

fuzzy logic

(Encyclopedia)fuzzy logic, a multivalued (as opposed to binary) logic developed to deal with imprecise or vague data. Classical logic holds that everything can be expressed in binary terms: 0 or 1, black or white, ...

hairdressing

(Encyclopedia)hairdressing, arranging of the hair for decorative, ceremonial, or symbolic reasons. Primitive men plastered their hair with clay and tied trophies and badges into it to represent their feats and qual...

symbiosis

(Encyclopedia)symbiosis sĭmbēōˈsĭs [key], the habitual living together of organisms of different species. The term is usually restricted to a dependent relationship that is beneficial to both participants (als...

Adams, Charles Francis, 1807–86, American public official

(Encyclopedia)Adams, Charles Francis, 1807–86, American public official, minister to Great Britain (1861–68), b. Boston; son of John Quincy Adams. After a boyhood spent in various European capitals, he was grad...