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pound

(Encyclopedia)pound, abbr. lb, unit of either mass or force in the customary system of English units of measurement. Two different pounds of mass are defined, one in the avoirdupois system of units and one in the T...

Quechua

(Encyclopedia)Quechua, Kechua kēchˈwä [key], linguistic family belonging to the Andean branch of the Andean-Equatorial stock of Native American languages (mainly in South America). Encompassing far more native ...

organic food

(Encyclopedia)organic food, food raised without chemicals and processed without additives. Under standards adopted by the U.S. Agriculture Dept. (USDA) in 2000 and fully effective in 2002, synthetic fertilizers and...

year

(Encyclopedia)year, time required for the earth to complete one orbit about the sun. The solar or tropical year is measured relative to the sun and is equal to 365 days, 5 hr, 48 min, 46 sec of mean solar time (see...

horology

(Encyclopedia)horology hōrŏlˈəjē [key], science of measuring time and technology of constructing instruments for its measurement or recording. Early measurements of the passage of time were based on observatio...

concrete

(Encyclopedia)concrete, structural masonry material made by mixing broken stone or gravel with sand, cement, and water and allowing the mixture to harden into a solid mass. The cement is the chemically active eleme...

Great Depression

(Encyclopedia)Great Depression, in U.S. history, the severe economic crisis generally considered to have been precipitated by the U.S. stock-market crash of 1929. Although it shared the basic characteristics of oth...

Kennedy, Robert Francis

(Encyclopedia)Kennedy, Robert Francis, 1925–68, American politician, U.S. Attorney General (1961–64), b. Brookline, Mass., younger brother of President John F. Kennedy and son of Joseph P. Kennedy. A graduate o...

elementary particles

(Encyclopedia)CE5 elementary particles, the most basic physical constituents of the universe. The first subatomic particle to be discovered was the electron, identified in 1897 by J. J. Thomson. After the...

sidereal year

(Encyclopedia)sidereal year, time required for the earth to complete an orbit of the sun relative to the stars. The sidereal year is 365 days, 6 hr, 9 min, 9.5 sec of mean solar time (see solar time). It is 20 min ...