Encyclopædia Britannica Australia -

Encyclopedias since 1768

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oratorio ... Orebro

oratorio: a large-scale musical composition on a sacred or semisacred subject, for solo voices, chorus, and orchestra. An oratorio's text is usually based on scripture, and the narration necessary to move from scene to scene is supplied by recitatives sung by ...
oratory: the rationale and practice of persuasive public speaking. It is immediate in its audience relationships and reactions, but it may also have broad historical repercussions. The orator may become the voice of political or social history.
oratory: in architecture, a small, private chapel (q.v.).
orb: emblem of royal power, usually made of precious metal and jewels and consisting of a sphere surmounted by a cross. The ball as a symbol of the cosmos, or of the universe as a harmonious whole, is derived from the ...
orb weaver: any spider of the family Araneidae (Argiopidae or Epeiridae) of the order Araneida, a large and widely distributed group noted for their orb-shaped webs. More than 2,500 species are known.
Orbigny, Alcide Dessalines d': founder of the science of micropaleontology.
Orbison, Roy: American singer-songwriter best remembered for his soaring voice, one of the most operatic in all rock music, and for his carefully crafted ballads of loneliness and heartache.
orbit: in astronomy, path of a body revolving around an attracting centre of mass, as a planet around the Sun or a satellite around a planet. In the 17th century, Johannes Kepler and Isaac Newton discovered the basic physical laws governing ...
orbital: in chemistry and physics, a mathematical expression, called a wave function, that describes properties characteristic of no more than two electrons in the vicinity of an atomic nucleus or of a system of nuclei as in a molecule. An orbital ...
orbital velocity: velocity sufficient to cause a natural or artificial satellite to remain in orbit. Inertia of the moving body tends to make it move on in a straight line, while gravitational force tends to pull it down. The orbital path, elliptical ...
Orbiting Astronomical Observatory: any of a series of unmanned U.S. scientific satellites developed to observe cosmic objects from above the Earth's atmosphere. OAO-2, launched Dec. 7, 1968, carried two large telescopes and a complement of spectrometers and other auxiliary devices. It weighed more ...
Orbiting Geophysical Observatory: any of a series of six unmanned scientific satellites launched by the United States from 1964 to 1969. Equipped with a complex of magnetometers, these orbiting satellites were designed to study the Earth's magnetosphere (i.e., zone of strong magnetic forces ...
orc: a mythical creature (such as a sea monster, a giant, or an ogre) of horrid form or aspect.
Orcagna, Andrea: the most prominent Florentine painter, sculptor, and architect of the mid-14th century.
orchard grass: (Dactylis glomerata), perennial pasture, hay, and forage grass of the family Poaceae. It has flat leaf blades and open, irregular, stiff-branched panicles (flower clusters).
Orchard, William Edwin: English ecumenical priest who strove for a closer understanding between Protestants and Roman Catholics. He entered Westminster College, Cambridge, to prepare for the Presbyterian ministry and in 1904 was ordained and became a minister at Enfield, Middlesex. After receiving a ...
Orchardson, Sir William Quiller: British portraitist and painter of historical and domestic genre scenes.
orchestra: instrumental ensemble of varying size and composition. Although applied to various ensembles found in Western and non-Western music, orchestra in an unqualified sense usually refers to the typical Western music ensemble of bowed stringed instruments complemented by wind and percussion ...
orchestration: the arrangement or composition of music for instruments, especially those found in an orchestra. See instrumentation.
orchestrina di camera: any of a group of small keyboard instruments related to the harmonium, invented and made by W.E. Evans of London. He patented them on Oct. 29, 1862.
Orchha: historic town, Tikamgarh district, Madhya Pradesh state, central India, on the Betwa River. The town, surrounded by thick jungle that long made it impregnable, was founded in 1531 and served until 1783 as the capital of the former Orchha princely ...
Orchha: former Rajput princely state of central India, founded in about 1500. In the early 17th century it was systematically devastated by the forces of the Mughal emperor Shah Jahan following the rebellion of the Bundela chief Jujhar Singh.
orchid: any member of the family Orchidaceae, a group of attractively flowered plants that composes the order Orchidales. There are from 400 to 800 genera of orchids, with at least 15,000 to as many as 35,000 species.
Orchidales: orchid order of monocotyledonous flowering plants, a division of the subclass Liliidae.
orchil: a violet dye obtained from some lichens by fermentation. It is also the term for any lichen that yields orchil (Roccella, Lecanora, Ochrolechin, and Evernia) and refers to any colour obtained from this dye.
Orchis: genus of orchids, family Orchidaceae, containing as many as 100 species native to Eurasia and North America. Each plant bears a single flower spike with many flowers and has egg-shaped, lobed, or forked tuberous roots. Most species have several leaves ...
orchitis: inflammation and swelling of the testes as a result of infection or physical injury. The testes are a pair of organs located in the scrotum of the male; they produce sperm cells for reproduction. Connected to the back of each ...
Orchomenus: ancient Boeotian town on a promontory on the north of the Copiac plain. The northernmost Mycenaean fortified town, it was a seat of the Minyae dynastic family and controlled a large part of Boeotia. In the Archaic period, Orchomenus was ...
Orczy, Baroness Emmuska: Hungarian-born British novelist, chiefly remembered as author of The Scarlet Pimpernel, one of the greatest popular successes of the 20th century.
Ord River: river in the Kimberley plateau region, northeastern Western Australia. It rises in the Albert Edward Range and follows an easterly and northerly course for 300 mi (500 km) to Cambridge Gulf. Chief tributaries are the Denham, Stirling, Panton, Wilson, Bow, ...
Ordainer: one of a committee of 21 nobles and prelates who opposed Edward II and framed a body of "Ordinances" intended to regulate his household and power.
ordeal: a trial or judgment of the truth of some claim or accusation by various means based on the belief that the outcome will reflect the judgment of supernatural powers and that these powers will ensure the triumph of right. Although ...
Ordelaffi Family: noble Italian family that ruled the town of Forli and neighbouring places in the Romagna during most of the 14th and 15th centuries. Little is known of their rise; a reference in Dante's Inferno indicates that Forli had passed effectively ...
order: in any of several styles of classical or Neoclassical architecture that are defined by the particular type of column and entablature they use as a basic unit. A column consists of a shaft together with its base and its capital. ...
order in council: in Great Britain, a regulation issued by the sovereign on the advice of the Privy Council; in modern practice, however, an order is issued only upon the advice of ministers, the minister in charge of the department concerned with the ...
Orderic Vitalis: English monk of Saint-Evroult in Normandy, a historian who in his Historia ecclesiastica left one of the fullest and most graphic accounts of Anglo-Norman society in his own day.
Orderville: town, Kane county, southwestern Utah, U.S., on the East Fork of the Virgin River, at an altitude of 5,250 feet (1,600 metres), 18 miles (29 km) north-northwest of Kanab. Settled in 1864, it was evacuated in 1866 because of Indian ...
ordinary differential equation: in mathematics, an equation relating a function f of one variable to its derivatives. (The adjective "ordinary" here refers to those differential equations involving one variable, as distinguished from such equations involving several variables, called partial differential equations.)
ordinary language analysis: method of philosophical investigation concerned with how verbal expressions are used in a particular, nontechnical, everyday language. The basic source for this school of thought is the later writings of the Viennese-born philosopher Ludwig Wittgenstein, followed by the contributions of ...
ordination: in Christian churches, a rite for the dedication and commissioning of ministers. The essential ceremony consists of the laying of hands of the ordaining minister upon the head of the one being ordained, with prayer for the gifts of the ...
Ordonez, Antonio: Spanish matador, generally considered to be the first-ranked bullfighter of the 1950s and '60s.
Ordonez, Bartolome: sculptor who was one of the originators of the Spanish school of Renaissance sculpture. Influenced by the masters of the Italian Renaissance, he evolved his own pure style, which was widely imitated after his early death.
Ordos Desert: desert on a plateau in the southern section of the Inner Mongolian autonomous ch'u (region), China. The Ordos fills the area inside the great northern bend of the Huang Ho (Yellow River) and is bounded by the provincial boundaries with ...
Ordovician Period: second oldest period of the Paleozoic Era, thought to have covered the span of time between 505 and 438 million years ago (see ), although radiometric age determinations may range from as much as 515 to 435 million years ago. ...
Ordu: city and port, northern Turkey, on the Black Sea. It lies at the mouth of the Melet River on the eastern slopes of Boztepe (1,800 feet [550 m]), which protects it against storms from the northwest. Ordu was the site ...
Ordyn-Nashchokin, Afanasy Lavrentyevich: statesman and diplomat who became the chief adviser on foreign affairs to Tsar Alexis of Russia (ruled 1645-76).
Ordzhonikidze, Grigory Konstantinovich: communist leader who played a major role in bringing Georgia under Soviet rule and in industrializing the Soviet Union.
ore: aggregate of economically important minerals that is sufficiently rich to enable separation of the minerals at a profit.
Ore Mountains: range of hills bounding the Bohemian Massif, extending 100 miles (160 km) along the German-Czech border, and reaching an average width of 25 miles (40 km). The Bohemian (southeastern) side of the range has a steep scarp face (2,000 to ...
Orebro: lan (county) of south-central Sweden. It extends from the Bergslagen mining region in the north to Lake Hjalmar in the east and Lake Vatter in the south. It comprises the traditional landskap (province) of Narke and parts of those of ...
Orebro: town and capital of Orebro lan (county), south-central Sweden. Orebro lies along the Svart River at its entrance into Lake Hjalmar. One of Sweden's oldest towns, it was already a commercial centre in the 13th century and played a prominent ...