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mental retardation

(Encyclopedia)mental retardation, below average level of intellectual functioning, usually defined by an IQ of below 70 to 75, combined with limitations in the skills necessary for daily living. Daily living skills...

leprosy

(Encyclopedia)leprosy or Hansen's disease hănˈsənz [key], chronic, mildly infectious malady capable of producing, when untreated, various deformities and disfigurements. It is caused by the rod-shaped bacterium ...

Kepler's laws

(Encyclopedia)CE5 Schematic representation of Kepler's second law: The areas ABF and A′B′F′ are equal and are swept out in equal intervals of time by a planet orbiting around the sun (at F). Kepler's laws...

Defense, United States Department of

(Encyclopedia)Defense, United States Department of, executive department of the federal government charged with coordinating and supervising all agencies and functions of the government relating directly to nationa...

pregnancy

(Encyclopedia)pregnancy, period of time between fertilization of the ovum (conception) and birth, during which mammals carry their developing young in the uterus (see embryo). The average duration of pregnancy in h...

Wellington, Arthur Wellesley, 1st duke of

(Encyclopedia)Wellington, Arthur Wellesley, 1st duke of, 1769–1852, British soldier and statesman. Wellington, “the iron duke,” with the soldier's taste for discipline and order and the aristocrat's distrus...

Stonehenge

(Encyclopedia)Stonehenge stōnˈhĕnjˌ [key], group of standing stones on Salisbury Plain, Wiltshire, S England. Preeminent among megalithic monuments in the British Isles, it is similar to an older and larger mon...

James II, king of England, Scotland, and Ireland

(Encyclopedia)James II, 1633–1701, king of England, Scotland, and Ireland (1685–88); second son of Charles I, brother and successor of Charles II. James made an effort to restore himself by landing in Irel...

carbon dioxide

(Encyclopedia)carbon dioxide, chemical compound, CO2, a colorless, odorless, tasteless gas that is about one and one-half times as dense as air under ordinary conditions of temperature and pressure. It does not bur...

seismology

(Encyclopedia)seismology sīzmŏlˈəjē, sīs– [key], scientific study of earthquakes and related phenomena, including the propagation of waves and shocks on or within the earth by natural or artificially genera...