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Rabanus Maurus
Frankish abbot, archbishop, and theologian whose encyclopaedic knowledge and numerous writings brought him the title Praeceptor Germaniae (“Teacher of Germany”).
Rabat
City (pop., 1994: city, 623,457; Rabat-Salé metro. area, 1,385,872), capital of Morocco.
rabbi
In Judaism, a person qualified by study of the Hebrew scriptures and the Talmud to serve as spiritual leader of a Jewish community or congregation.
rabbinic Judaism
Principal form of Judaism that developed after the fall of the Second Temple of Jerusalem (AD 70).
rabbit
Any small, bounding, gnawing mammal of the family Leporidae.
Rabéarivelo, Jean-Joseph
Malagasy writer.
Rabelais, François
French writer and priest.
Rabi, I(sidor) I(saac)
Polish-born U.S. physicist.
rabies
Acute, usually fatal infectious disease of warm-blooded animals that attacks the central nervous system.
Rabin, Yitzhak
First native-born prime minister of Israel.
raccoon
Any of seven species of omnivorous, nocturnal carnivores (genus Procyon, family Procyonidae) characterized by a bushy, ringed tail and a black mask on the face.
race
Term once commonly used in physical anthropology to denote a division of humankind possessing traits that are transmissible by descent and sufficient to characterize it as a distinct human type (e.g., Caucasoid, Mongoloid, Negroid).
racemate
Mixture of equal quantities of two enantiomers, substances whose molecular structures are mirror images of one another (see isomer).
racer
Any of several slender, swift snakes (subspecies of Coluber constrictor, family Colubridae) of North and Central America and Asia.
Rachel
In the book of Genesis, one of Jacob's two wives.
Rachmaninoff, Sergey (Vassilyevich)
Russian-born U.S. composer and pianist.
Racine, Jean (-Baptiste)
French playwright.
racism
Any action, practice, or belief that reflects the racial worldview—the ideology that humans are divided into separate and exclusive biological entities called “races,” that there is a causal link between inherited physical traits and traits of personality, intellect, morality, and other cultural behavioral features, and that some “races” are innately superior to others.
rack and pinion
Mechanical device consisting of a bar of rectangular cross section (the rack), having teeth on one side that mesh with teeth on a small gear (the pinion).
rackets
Game for two or four players with ball and racket on a four-walled court.
Rackham, Arthur
British artist and illustrator.
racquetball
Game similar to handball but played with racquets.
radar
System that uses electromagnetic echoes to detect and locate objects.
Radcliffe, Ann
English gothic novelist.
Radcliffe-Brown, A(lfred) R(eginald)
British social anthropologist.
Radek, Karl (Bernhardovich)
Russian communist politician.
Radetzky, Joseph, Count
Austrian army officer.
Radha
In Hindu mythology, mistress of the god Krishna when he lived among the cowherds of Vrndavana.
radial engine
Type of internal-combustion engine used mainly in small airplanes, in which the cylinders (ranging from five to as many as 28, depending on engine size) are mounted in a circle around the crankshaft, sometimes in banks of two or more.
radiant heating
Heating system in which heat is transmitted by radiation from a heated surface.
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