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Cheboygan ... Chemung
Cheboygan
city, seat (1853) of Cheboygan county, northern Michigan, U.S. The city lies along the Cheboygan River as it enters Lake Huron near the eastern end of the Straits of Mackinac. ...
Chebyshev's inequality
in probability theory, a theorem that characterizes the dispersion of data away from its mean (average). The general theorem is attributed to the 19th-century Russian mathematician Pafnuty Chebyshev, though credit ...
Chebyshev, Pafnuty Lvovich
founder of the St. Petersburg mathematical school (sometimes called the Chebyshev school), who is remembered primarily for his work on the theory of prime numbers and on the approximation of ...
Chechaouene
Muslim holy city, northern Morocco, situated in the Rif mountain range. Founded in 1471 by the warrior Abu Youma and later moved by Sidi Ali ibn Rachid to its present ...
Chechnya
republic in southwestern Russia, situated on the northern flank of the Greater Caucasus range. Chechnya is bordered by Russia proper on the north, Dagestan republic on the east and southeast, ...
check
bill of exchange drawn on a bank and payable on demand; it has become the chief form of money in the domestic commerce of developed countries. As a written order ...
checkered beetle
any of the approximately 3,000 species of the insect family Cleridae (order Coleoptera). Checkered beetles occur throughout the world, mainly in the tropics; the common name derives from their markings ...
checkers
board game, one of the world's oldest games. Checkers is played by two persons who oppose each other across a board of 64 light and dark squares, the same as ...
checkerwork
in architecture, masonry built of two materials, usually stone and flint or stone and brick, so arranged as to make a checkerboard pattern and to give variety in texture and ...
checks and balances
principle of government under which separate branches are empowered to prevent actions by other branches and are induced to share power. Checks and balances are applied primarily in constitutional governments. ...
Cheddar
village ("parish"), Sedgemoor district, administrative and historic county of Somerset, England, at the mouth of a spectacular limestone gorge in the Mendip Hills. The gorge (now owned by the National ...
cheddar
hard cow's-milk cheese named for the district of its origin in the southwestern county of Somerset, England. Cheddar is one of England's oldest cheeses. The original, so-called farmhouse variety remains ...
Chediak-Higashi syndrome
a rare inherited childhood disease characterized by the inability of white blood cells called phagocytes to destroy invading microorganisms.
Cheduba Island
island in the Bay of Bengal, southwestern Myanmar (Burma). It lies about 30 miles (50 km) west of Taungup on the Arakan Coast and is separated from Ramree Island to ...
Cheektowaga
town (township), Erie county, western New York, U.S. It lies immediately east of Buffalo, on Ellicott, Scajaquada, and Cayuga creeks, near Lake Erie. Originally part of the Holland Land Purchase ...
cheese
nutritious food consisting primarily of the curd, the semisolid substance formed when milk curdles, or coagulates. Curdling occurs naturally if milk is not used promptly: it sours, forming an acid ...
cheetah
one of the world's most recognizable cats, known especially for its speed. Cheetahs' sprints have been measured at a maximum of 114 km (71 miles) per hour, and they routinely ...
Cheever, Ezekiel
a leading schoolmaster in colonial British America.
Cheever, John
American short-story writer and novelist whose work describes, often through fantasy and ironic comedy, the life, manners, and morals of middle-class, suburban America. Cheever has been called "the Chekhov of ...
Chegutu
town, central Zimbabwe. Named originally for Henry Hartley, who discovered gold in the vicinity, it was founded in 1891 on the Umfuli River but about 1900 was moved 18 miles ...
Chehab, Fuad
Lebanese army officer and statesman who served as president of Lebanon in 1958-64. Noted for his honesty and integrity, he brought a measure of stability to the government and to ...
Cheilostomata
major division of the bryozoans (small, colonial, aquatic invertebrate animals) that first appeared during the Jurassic period (208 to 144 million years ago). Individual members of the cheilostome colony are ...
Cheirolepis
extinct genus of primitive fishes whose fossils are found in European and North American rocks of the Devonian period (408 to 360 million years ago). The genus Cheirolepis is representative ...
Cheju
city and provincial capital, Cheju do (province), on the northern coast of Cheju Island, off the southern coast of South Korea. It is the island's largest city and has its ...
Cheju Island
island and (since 1946) do (province) of South Korea. It is in the East China Sea, 60 miles (100 km) southwest of Cholla-nam province, of which it formerly was a ...
Cheka
early Soviet secret police agency and a forerunner of the KGB (q.v.).
Cheke, Sir John
English humanist and supporter of the Protestant Reformation who, as the poet John Milton said, "taught Cambridge and King Edward Greek" and who, with his friend Sir Thomas Smith, discovered ...
Chekhov, Anton
major Russian playwright and master of the modern short story. He was a literary artist of laconic precision who probed below the surface of life, laying bare the secret motives ...
Chekiang
sheng (province) of China. It is the third smallest province of China and also one of the most densely populated and affluent. Its area is 39,300 square ...
Chelan, Lake
lake, north-central Washington, U.S., extending 55 miles (88 km) through a glacier-carved valley on the eastern edge of the Cascade Range. Lying just outside North Cascades National Park near the ...
chelate
any of a class of coordination or complex compounds consisting of a central metal atom attached to a large molecule, called a ligand, in a cyclic or ring structure. An ...
Chelcicky, Peter
Czech religious and political writer, the foremost thinker of the 15th-century Czech Hussite Reformation movement.
Chelif River
the longest and most important river of Algeria. Its farthest tributary, the Sebgag River, rises in the Amour ranges of the Saharan Atlas Mountains near Aflou. Crossing the Hauts Plateaux ...
Cheliff, Ech-
town, northern Algeria. It lies along the Chelif River, south of the Mediterranean port of Tenes. It was founded by the French in 1843 on the site of the ancient ...
Chellean industry
an early Stone Age industry characterized by crudely worked hand axes. The implements from Chelles in France that gave the industry its name are now grouped with the Acheulian industry. ...
Chelles
town, eastern suburb of Paris, in Seine-et-Marne departement, Paris region, north-central France, near the Marne River. It is the site of ancient Calae and has ruins of the 7th-century Abbey ...
Chelm
city, Lubelskie wojewodztwo (province), eastern Poland. The city is located on the Uherka River, a tributary of the Bug River, 15 miles (24 km) west of the ...
Chelmno
Nazi German extermination camp on the Ner River, a tributary of the Warta, in western Poland. It opened in December 1941 and closed in January 1945 and was operated to ...
Chelmsford
town (township), Middlesex county, northeastern Massachusetts, U.S. It lies 24 miles (39 km) north of Boston; the city of Lowell is adjacent to the northeast. Settled in 1633, it was ...
Chelmsford
town and borough (district), administrative and historic county of Essex, England. It lies in the valley of the River Chelmer northeast of Greater London in south-central Essex.
Chelmsford, Frederic John Napier Thesiger, 1st Viscount, Baron Chelmsford Of Chelmsford
English colonial administrator and statesman who served for several years as governor of Queensland and New South Wales before becoming viceroy of India; he helped to institute reforms increasing Indian ...
Chelsea
city, Suffolk county, eastern Massachusetts, U.S. A northeastern suburb of Boston, it lies on the estuary of the Mystic River and is joined to Charlestown by a road bridge. Settled ...
Chelsea porcelain
soft-paste porcelain made at a factory in Chelsea, London, established in 1743 by Charles Gouyn and Nicolas Sprimont, the latter a silversmith. By the 1750s the sole manager was Sprimont, ...
Cheltenham
town and borough (district), administrative and historic county of Gloucestershire, England. It is situated where the River Chelt, a tributary of the River Severn, breaks through the western edge of ...
Chelyabinsk
oblast (province), west-central Russia. It is sited on the eastern flank of the Ural Mountains; a winding panhandle extends across to the western slopes. In the extreme east, the oblast ...
Chelyabinsk
city and administrative centre, Chelyabinsk oblast (province), west-central Russia. It lies on the eastern flank of the Ural Mountains and on the Miass River.
chemical association
the aggregation of atoms or molecules into larger units held together by forces weaker than chemical bonds that bind atoms in molecules. The term is usually restricted to the formation ...
Chemical Banking Corporation
former American bank holding company that merged with The Chase Manhattan Corporation in 1996.
chemical bonding
any of the interactions that account for the association of atoms into molecules, ions, crystals, and other stable species that make up the familiar substances of the everyday world. When ...
chemical compound
any substance composed of identical molecules consisting of atoms of two or more elements.
chemical dependency
the body's physical and/or psychological addiction to a psychoactive (mind-altering) substance, such as narcotics, alcohol, or nicotine. Physical dependency on such chemicals as prescription drugs or alcohol stems from repetitive ...
chemical element
any substance that cannot be decomposed into simpler substances by ordinary chemical processes. Elements are the fundamental materials of which all matter is composed.
chemical engineering
the development of processes and the design and operation of plants in which materials undergo changes in their physical or chemical state. Applied throughout the process industries, it is founded ...
chemical equilibrium
a condition in the course of a reversible chemical reaction in which no net change in the amounts of reactants and products occurs. A reversible chemical reaction is one in ...
chemical formula
any of several kinds of expressions of the composition or structure of chemical compounds. The forms commonly encountered are empirical, molecular, structural, and projection formulas.
chemical hydrology
subdivision of hydrology that deals with the chemical characteristics of the water on and beneath the surface of the Earth. Water in all forms and modes of occurrence is affected ...
chemical indicator
any substance that gives a visible sign, usually by a colour change, of the presence or absence of a threshold concentration of a chemical species, such as an acid or ...
chemical industry
complex of processes, operations, and organizations engaged in the manufacture of chemicals and their derivatives.
chemical intermediate
any chemical substance produced during the conversion of some reactant to a product. Most synthetic processes involve transformation of some readily available and often inexpensive substance to some desired product ...
chemical precipitation
formation of a separable solid substance from a solution, either by converting the substance into an insoluble form or by changing the composition of the solvent to diminish the solubility ...
chemical reaction
any type of chemical process in which substances are changed into different substances, as differentiated from other kinds of changes-those of position or of form-undergone by matter. Chemical reactions are ...
chemical symbol
short notation derived from the scientific name of a chemical element-e.g., S for sulfur and Si for silicon. Sometimes the symbol is derived from the Latin name-e.g., Au for aurum, ...
chemical synthesis
the construction of complex chemical compounds from simpler ones. It is the process by which many substances important to daily life are obtained. It is applied to all types of ...
chemical warfare
the use of chemical compounds, usually toxic agents, in warfare, and also the methods of combating such agents. Though smoke, which is used for camouflage or to confuse an enemy, ...
chemiluminescence
emission of electromagnetic radiation during the course of chemical reactions. Such radiation, whether ultraviolet, visible, or infrared, is most commonly generated by oxidation. The radiation can usually be ascribed to ...
chemin de fer
French card game played mainly in European and Latin American casinos. The game is played by up to 12 players, on a kidney-shaped table; the object is to total 9 ...
chemistry
the science that deals with the properties, composition, and structure of substances (defined as elements and compounds), the transformations they undergo, and the energy that is released or absorbed during ...
chemistry
the science that deals with the properties, composition, and structure of substances (defined as elements and compounds), the transformations that they undergo, and the energy that is released or absorbed ...
Chemnitz
city, Saxony Land (state), eastern Germany. The city lies along the Chemnitz River, at the north foot of the Ore Mountains, southwest of Dresden. It began as ...
Chemnitz, Martin
leading German theologian who was known, with reference to Martin Luther, as "the second Martin" and who helped unify the Lutheran church following the Reformation.
chemoreception
process by which organisms respond to chemical stimuli. The process begins when chemical stimuli come in contact with chemoreceptors, specialized cells in the body that convert (transduce) the immediate effects ...
Chemosh
ancient West Semitic deity, revered by the Moabites as their supreme god. Little is known about Chemosh; although King Solomon of Israel built a sanctuary to him east of Jerusalem ...
chemosterilant
any chemical compound used to control economically destructive or disease-causing pests (usually insects) by causing temporary or permanent sterility of one or both of the sexes or preventing maturation of ...
chemotaxy
method of biological classification based on similarities in the structures of certain compounds among the organisms being classified. Proponents of this taxonomic method argue that proteins, being more closely controlled ...
chemotherapy
the treatment of diseases by chemical compounds. Chemotherapeutic drugs were originally those employed against infectious microbes, but the term has been broadened to include anticancer and other drugs.
Chemung
county, south-central New York state, U.S., bordered by Pennsylvania to the south. It consists of a hilly region drained by the Chemung River (which bisects the county roughly north-south) and ...