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Agnesi, Maria Gaetana ... Aguan River
Agnesi, Maria Gaetana
Italian mathematician and philosopher, considered to be the first woman in the Western world to have achieved a reputation in mathematics.
Agnew, Spiro T.
39th vice president of the United States (1969-73) in the Republican administration of President Richard M. Nixon. He was the second person to resign the nation's second highest office (John C. Calhoun was the first in 1832) and the first ...
Agni
(Sanskrit: "Fire"), fire-god of the Hindus, second only to Indra in the Vedic mythology of ancient India. He is equally the fire of the sun, of lightning, and of the hearth that men light for purposes of worship. As the ...
Agnihotri, Shiv Narayan
Hindu founder of an atheistic society called Deva Samaj ("Society of God").
Agnon, S.Y.
Israeli writer who was one of the leading modern Hebrew novelists and short-story writers. In 1966 he was the corecipient, with Nelly Sachs, of the Nobel Prize for Literature.
agnosticism
(from Greek agnostos, "unknowable"), strictly speaking, the doctrine that humans cannot know of the existence of anything beyond the phenomena of their experience. The term has come to be equated in popular parlance with skepticism about religious ...
Agnostus
genus of trilobites (an extinct group of aquatic arthropods) found as fossils in rocks of Early Cambrian to Late Ordovician age (those deposited from 540 to 438 million years ago). The agnostids were generally small, with only two thoracic segments ...
Agnus Dei
designation of Jesus Christ in Christian liturgical usage. It is based on the saying of John the Baptist: "Behold, the Lamb of God, who takes away the sin of the world!" (John 1:29). In the Roman Catholic liturgy the Agnus ...
Agobard, Saint
archbishop of Lyon from 816, who was active in political and ecclesiastical affairs during the reign of the emperor Louis I the Pious. He also wrote theological and liturgical treatises.
agon
debate or contest between two characters in Attic comedy, constituting one of several formal conventions in these highly structured plays. The Old Comedy of Greece, introduced into Dionysian festivals in 487 BC and surviving in the works of Aristophanes, adhered ...
agonism
survivalist animal behaviour that includes aggression, defense, and avoidance. The term is favoured by biologists who recognize that the behavioral bases and stimuli for approach and fleeing are often the same, the actual behaviour exhibited depending on other factors, especially ...
agora
in ancient Greek cities, an open space that served as a meeting ground for various activities of the citizens. The name, first found in the works of Homer, connotes both the assembly of the people as well as the physical ...
Agoracritus
Greek sculptor said to have been the favourite pupil of Phidias. His most renowned work is the statue of Nemesis at Rhamnous, Greece, part of the head of which is in the British Museum, while fragments of the pedestal reliefs ...
Agostino Di Duccio
early Renaissance sculptor whose work is characterized by its linear decorativeness. His early work shows the influence of Donatello and Michelozzo, whom he assisted in adorning SS. Annunziata in Florence.
Agostino Di Giovanni
late Gothic sculptor, best known for his work, with Agnolo di Ventura, on the tomb of Guido Tarlati.
Agoult, Marie de Flavigny, comtesse d'
writer famous for her position in Parisian society in the 1840s and for her liaison with the composer Franz Liszt.
agouti
any of about a dozen species of tropical American rodents resembling the small forest-dwelling hoofed animals of tropical Africa and Asia (see chevrotain; duiker; royal antelope). Agoutis weigh up to 6 kg (13 pounds), with an elongated body measuring up ...
Agra
city, west-central Uttar Pradesh state, north-central India, on the Yamuna (Jumna) River. Founded by Sikandar Lodi in the early 16th century, it was the Mughal capital during some periods of their empire. In the late 18th century the city fell ...
Agramonte y Simoni, Aristides
physician, pathologist, and bacteriologist, a member of the Reed Yellow Fever Board of the U.S. Army that discovered (1901) the role of the mosquito in the transmission of yellow fever.
agranulocytosis
acute infection characterized by severe sore throat, fever, and prostration and associated with an extreme reduction of the white blood cells (leukopenia), particularly the cell types known as neutrophils (neutropenia).
Agrarian League
extraparliamentary organization active under the German empire from 1893. Formed to combat the free-trade policies (initiated in 1892) of Chancellor Leo, Graf (count) von Caprivi, the league worked for farmers' subsidies, import tariffs, and minimum prices. Caprivi's successor promised to ...
Agre, Peter
American doctor, corecipient of the Nobel Prize for Chemistry in 2003 for his discovery of water channels in cell membranes. He shared the award with Roderick MacKinnon, also of the United States.
Agreda, Maria de
abbess and mystic. In 1620 she took her vows as a Franciscan nun and in 1627 became abbess of a Franciscan monastery in Agreda, retaining this office, except for a brief period, until her death.
Agri
city, in the highlands of eastern Turkey. It lies 5,380 feet (1,640 metres) above sea level in the valley of the Murat River, a tributary of the Euphrates River. The town is a centre for trade in livestock and livestock ...
Agri Decumates
in antiquity, the Black Forest and adjoining areas of what is now southwestern Germany between the Rhine, Danube, and Main rivers. The name may imply earlier occupation by a tribe with 10 cantons. The Romans under the Flavian emperors began ...
agribusiness
agriculture regarded as a business; more specifically, that part of a modern national economy devoted to the production, processing, and distribution of food and fibre products and by-products.
Agricola, Alexander
composer of the late Burgundian polyphonic school.
Agricola, Georgius
German scholar and scientist known as "the father of mineralogy." While a highly educated classicist and humanist, well regarded by scholars of his own and later times, he was yet singularly independent of the theories of ancient authorities. He was ...
Agricola, Gnaeus Julius
Roman general celebrated for his conquests in Britain. His life is set forth by his son-in-law, the historian Tacitus.
Agricola, Johann
Lutheran Reformer, friend of Martin Luther, and advocate of antinomianism, a view asserting that Christians are freed by grace from the need to obey the Ten Commandments. At Wittenberg, Agricola was persuaded by Luther to change his course of study ...
Agricola, Martin
composer, teacher, and writer on music, one of the first musicians to concern himself with the needs of the Reformed churches and to publish musical treatises in the vernacular.
Agricola, Rodolphus
Dutch humanist who, basing his philosophy on Renaissance ideas, placed special emphasis on the freedom of the individual and the complete development of the self, from both an intellectual and a physical standpoint. His ideas influenced Desiderius Erasmus, another Dutch ...
Agricultural Adjustment Administration
in American history, major New Deal program to restore agricultural prosperity by curtailing farm production, reducing export surpluses, and raising prices. The Agricultural Adjustment Act (May 1933) was an omnibus farm-relief bill embodying the schemes of the major national farm ...
agricultural economics
study of the allocation, distribution, and utilization of the resources used, along with the commodities produced, by farming. Agricultural economics plays a role in the economics of development, for a continuous level of farm surplus is one of the wellsprings ...
agricultural sciences, the
sciences dealing with food and fibre production and processing. They include the technologies of soil cultivation, crop cultivation and harvesting, animal production, and the processing of plant and animal products for human consumption and use.
agricultural technology
application of techniques to control the growth and harvesting of animal and vegetable products.
agriculture
the science or art of cultivating the soil, growing and harvesting crops, and raising livestock. The art of making land more productive is practiced throughout the world-in some areas by methods not far removed from the conditions of several thousands ...
agriculture, history of
history of the practice of cultivating the soil, harvesting crops, and raising livestock from its origins in prehistoric times to the present.
Agrigento
capital of Agrigento provincia, near the southern coast of Sicily, Italy. It lies on a plateau encircled by low cliffs overlooking the junction of the Drago (ancient Hypsas) and San Biagio (Acragas) rivers and is dominated from the north by ...
Agrihan
one of the Mariana Islands, part of the U.S. Commonwealth of the Northern Mariana Islands. It lies in the western Pacific Ocean, 350 miles (563 km) north of Guam. An active volcano that last erupted in 1917, it has a ...
agrimony
any plant of the genus Agrimonia, of the rose family (Rosaceae). The name particularly denotes A. eupatoria, an herbaceous, hardy perennial that is native to Europe but is widespread in other northern temperate regions, where it grows in hedge banks ...
Agrinion
chief town of the nomos (department) of Aetolia and Acarnania, west-central Greece. It lies 4 miles (6 km) northwest of Lake Trikhonis, about midway between the Ionian Sea and the Gulf of Patras. Formerly called Vrakhori (an ...
Agrionia
(from Greek agrios, "wild," or "savage"), Greek religious festival celebrated annually at Orchomenus in Boeotia and elsewhere in honour of the wine god Dionysus. The tradition is that the daughters of Minyas, king of Orchomenus, having despised the rites of ...
Agrippa
ancient Greek philosophical skeptic. He is famous for his formulation of the five tropes, or grounds for the suspension of judgment, that summarize the method of argument of Greek skeptics generally.
Agrippa von Nettesheim, Heinrich Cornelius
court secretary to Charles V, physician to Louise of Savoy, exasperating theologian within the Catholic Church, military entrepreneur in Spain and Italy, acknowledged expert on occultism, and philosopher. His tempestuous career also included teaching at Dole and Pavia universities, appointment ...
Agrippa, Marcus Vipsanius
powerful deputy of Augustus, the first Roman emperor. He was chiefly responsible for the victory over Mark Antony at the Battle of Actium in 31 BC, and during Augustus' reign he suppressed rebellions, founded colonies, and administered various parts of ...
Agrippina The Elder
granddaughter of the emperor Augustus and a major figure in the succession struggles in the latter part of the reign of Tiberius (ruled AD 14-37).
Agrippina The Younger
mother of the Roman emperor Nero and a powerful influence on him during the early years of his reign (54-68).
agrostology
the branch of botany concerned with the study of grasses, especially their classification. In 1708 the German botanist Johann Scheuchzer wrote Agrostographiae Helveticae Prodromus, a taxonomic paper on grasses that some authors consider to mark the birth of agrostology. Many ...
Aguadilla
town, northwestern Puerto Rico. The town is a port on a wide bay formed on the south by the hills of Punta Higuero (Jiguera) and on the north by Punta Borinquen, the northwestern corner of the island. It was established ...
Aguan River
river in northern Honduras, 150 mi (240 km) in length. After rising in the central highlands west of Yoro, it descends to the northeast between the Cerros de Cangreja and the Sierra de la Esperanza to the coastal lowlands, on ...
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