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  • ogum (alphabetic script)
    alphabetic script dating from the 4th century ad, used for writing the Irish and Pictish languages on stone monuments; according to Irish tradition, it was also used for writing on pieces of wood, but there is no material evidence for this. In its simplest form, ogham consists of four sets of strokes, or notches, each set containing five letters ...
  • Ogun (deity)
    In traditional Itsekiri religion, Oritse is the supreme deity and creator of the world. Among the other deities are Umale Okun, god of the sea, and Ogun, god of iron and war. Divination may be accomplished by men skilled in consulting the Ifa oracle, and ceremonies are performed to the ancestors on various occasions....
  • Ogun (state, Nigeria)
    state, western Nigeria, created in 1976 and comprising former Abeokuta and Ijebu provinces of former Western state, the latter carved out of former Western region in 1967. Ogun is bounded by Oyo and Osun states to the north, Lagos state to the south, Ondo state to the east, and the Republic of Benin to the west. It is covered predominantly by tropical rain forest and has wooded savanna in the nor...
  • Ogunde Concert Party (Nigerian theatre)
    ...playwright, actor, theatre manager, and musician, who was a pioneer in the field of Nigerian folk opera (drama in which music and dancing play a significant role). He was the founder of the Ogunde Concert Party (1945), the first professional theatrical company in Nigeria. Often regarded as the father of Nigerian theatre, Ogunde sought to reawaken interest in his country’s indigenous......
  • Ogunde, Hubert (Nigerian playwright)
    Nigerian playwright, actor, theatre manager, and musician, who was a pioneer in the field of Nigerian folk opera (drama in which music and dancing play a significant role). He was the founder of the Ogunde Concert Party (1945), the first professional theatrical company in Nigeria. Often regarded as the father of Nigerian theatre, Ogunde sought to reawaken interest in his country...
  • Ogunmola, Elijah Kolawole (Nigerian dramatist)
    Nigerian actor, mime, director, and playwright who took Yoruba folk opera (drama that combines Christian themes with traditional Yoruban folklore, music and dancing, and music popular in urban culture) and developed it into a serious theatre form through his work with his Ogunmola Traveling Theatre (founded c. 1947). He was also widely regarded as one of the most brillian...
  • Ogunmola, Kola (Nigerian dramatist)
    Nigerian actor, mime, director, and playwright who took Yoruba folk opera (drama that combines Christian themes with traditional Yoruban folklore, music and dancing, and music popular in urban culture) and developed it into a serious theatre form through his work with his Ogunmola Traveling Theatre (founded c. 1947). He was also widely regarded as one of the most brillian...
  • Ogurchin (island, Turkmenistan)
    ...based partly on underwater relief and partly on hydrologic characteristics. The sea contains as many as 50 islands, mostly small. The largest are Chechen, Tyuleny, Morskoy, Kulaly, Zhiloy, and Ogurchin....
  • Oğuz (people)
    confederation of Turkic peoples whose homeland, until at least the 11th century ad, was the steppes of central Asia and Mongolia. The Orhon inscriptions, describing an early Turkic people, probably refer to the Oğuz. The Seljuqs, who comprised one branch of the Oğuz, controlled an empire stretching from the Amu Darya to the Persian Gulf and from the I...
  • Oğuz Turkic languages
    The Turkic languages may be classified, using linguistic, historical, and geographic criteria, into a southwestern (SW), a northwestern (NW), a southeastern (SE), and a northeastern (NE) branch. Chuvash and Khalaj form separate branches....
  • Ogy’gia (Greek mythology)
    ...fruit, vegetables, grapes, and livestock. Fishing is also important, and there is a cottage lace industry. The island is linked with Malta by ferry service. Gozo is held to be the island of Ogy’gia, in Greek legend, where the sea nymph Calypso entertained Odysseus. Pop. (2005 est.) 31,049....
  • Ogygion (Greece)
    major city of Boeotia nomós (department), northwest of Athens, Greece, and one of the chief cities and powers of ancient Greece. On the acropolis of the ancient city stands the present commercial and agricultural centre of Thebes. It is situated on a low ridge dividing the surrounding plain; the modern city is the seat of the Greek Orthodox bishop of Thebes and Levádhia. It ha...
  • Ogyū Sorai (Japanese scholar)
    one of the foremost Japanese scholars of Chinese culture and a leading Confucianist. Ogyū stressed the pragmatic application of Confucianism to promote social and political reforms by means of uniform, rational laws. He is also noted for his appreciative commentary on the revered shogunate ruler and administrative reformer Tokugawa Ieyasu (1543–1616)....
  • OH 13 (fossil)
    ...into a gully. Some of the teeth survived, but the cranium was broken into many small fragments; only the top of the braincase, or vault, has been pieced back together. These two skulls are called OH 13 and OH 16....
  • OH 16 (fossil)
    ...gully. Some of the teeth survived, but the cranium was broken into many small fragments; only the top of the braincase, or vault, has been pieced back together. These two skulls are called OH 13 and OH 16....
  • OH 24 (fossil)
    Since 1964 more material has been discovered, not only at Olduvai but at other African localities as well. One intriguing specimen is OH 24. This cranium is more complete than others from Olduvai. Because some of the bones are crushed and distorted, however, the face and braincase are warped. OH 24 may differ from Australopithecus in brain size and dental characteristics, but it......
  • OH 62 (fossil)
    ...discovery was reported from Olduvai Gorge in 1986. A jaw with teeth and skull fragments as well as pieces of a right arm and both legs were found. The bones seem to represent one individual, called OH 62. Although the skull is shattered, enough of the face is preserved to suggest similarities to early Homo. The find is especially important because of the limbs, which show that OH...
  • OH 7 (fossil)
    Apart from the original discovery of the jaw, cranial, and hand bones from a juvenile individual called Olduvai Hominid 7 (OH 7), additional fossils from Olduvai have been ascribed to H. habilis. Pieces of another thin-walled cranium along with upper and lower jaws and teeth came to light in 1963. Just a month later a third skull was found, but these bones had been trampled by......
  • OH 9 (fossil)
    ...the more convincing evidence for the existence of H. erectus in Africa came with the discovery in 1960 of a partial braincase at Olduvai Gorge in Tanzania. This fossil, catalogued as OH 9, was excavated by Louis S.B. Leakey and is probably about 1.2 million years old. Olduvai Gorge has since yielded additional cranial remains, jaws, and limb bones of H. erectus.......
  • Oh Dad, Poor Dad, Mama’s Hung You in the Closet and I’m Feelin’ So Sad (work by Kopit)
    American playwright best known for Oh Dad, Poor Dad, Mama’s Hung You in the Closet and I’m Feelin’ So Sad (1960). Subtitled “a pseudoclassical tragifarce in a bastard French tradition,” the play parodies the Theater of the Absurd, the Oedipus complex, and the conventions of avant-garde drama....
  • OH group (chemistry)
    Water and alcohols have similar properties because water molecules contain hydroxyl groups that can form hydrogen bonds with other water molecules and with alcohol molecules, and likewise alcohol molecules can form hydrogen bonds with other alcohol molecules as well as with water. Because alcohols form hydrogen bonds with water, they tend to be relatively soluble in water. The hydroxyl group is......
  • ¡Oh hada cibernética! (work by Belli)
    ...his fate as a frustrated, powerless poet who is forced to work at a mundane office job and feels perpetually humiliated by his lowly status and unrewarding labour. In such books as ¡Oh hada cibernética! (1961; “O Cybernetic Fairy”), Belli creates a number of pseudoclassical figures to whom he addresses his complaints: these include Fisco, the god of......
  • Oh Sadaharu (Japanese baseball player)
    professional baseball player who played for the Tokyo Yomiuri Giants in the Japanese Central League for 22 seasons between 1959 and 1980 who holds the record for the most home runs ever hit. (See also Japanese baseball leagues). He is among the most revered of Japan’s sporting figures. Oh led the league in hitting 5 times, led ...
  • Oh! What a Lovely War (work by Littlewood)
    ...the presentations. After the success in 1955 of Miller’s dramatic version of The Good Soldier Schweik, by Jaroslav Hašek, her influence grew. Oh! What a Lovely War (1963), an original evocation and criticism of World War I using popular songs of the period, projected newspaper headlines, and other devices to emphasize its message,....
  • O’Hagan, Martin (Northern Irish journalist)
    Northern Irish journalist (b. June 23, 1950, Lurgan, County Armagh [now in Craigavon district], N.Ire.—d. Sept. 28, 2001, Lurgan), was a former member of the Official Irish Republican Army (IRA) and the first working journalist to be murdered in Northern Ireland since the beginning of the “Troubles” in the late 1960s. O’Hagan, who was born a Roman Catholic, joined the m...
  • O’Hagan, Owen Martin (Northern Irish journalist)
    Northern Irish journalist (b. June 23, 1950, Lurgan, County Armagh [now in Craigavon district], N.Ire.—d. Sept. 28, 2001, Lurgan), was a former member of the Official Irish Republican Army (IRA) and the first working journalist to be murdered in Northern Ireland since the beginning of the “Troubles” in the late 1960s. O’Hagan, who was born a Roman Catholic, joined the m...
  • Ohain, Hans Joachim Pabst von (German designer)
    German designer of the first operational jet engine....
  • Ohan (work by Uno)
    ...the narrative in the voice of Tenguya Hisakichi, a carver of Bunraku puppets, as though she were telling his own story, a device she would later use in perhaps her finest work, the novella Ohan (1957; Eng. trans. as Ohan in The Old Woman, the Wife, and the Archer). Published 10 years after she had begun writing it, Ohan tells the story of a......
  • Ohara (Japanese art school)
    Japanese school of floral art, founded by Ohara Unshin in the early 20th century, which introduced the moribana style of naturalistic landscapes in shallow, dishlike vases. The moribana style, while retaining a basic triangular structure in its floral arrangements, is in the ...
  • Ohara Art Museum (museum, Kurashiki, Japan)
    ...to automobile production. After 1964 the industrial centre moved south, where petrochemical and heavy chemical plants face the Inland Sea. Kurashiki is also a cultural centre that houses the Ōhara Art Museum. Pop. (2005) 469,377....
  • O’Hara, Frank (American poet)
    American poet who gathered images from an urban environment to represent personal experience....
  • O’Hara, John Henry (American author)
    American novelist and short-story writer whose fiction stands as a social history of upwardly mobile Americans from the 1920s through the 1940s....
  • Ohārā Unshin (Japanese artist)
    (Japanese: “heaped-up flowers”), in Japanese floral art, a style of arranging in which naturalistic landscapes are constructed in low dishlike vases. Developed by Ohara Unshin, founder of the Ohara school of floral art, moribana breaks with the rigid structural rules of classical floral art; it sometimes incorporates flowers imported from Western countries and uses the basic....
  • O’Hare International Airport (airport, Chicago, Illinois, United States)
    ...O’Hare, a wartime naval air hero, while Municipal was renamed Midway for the critical 1942 Allied battle victory in the Pacific. Long the undisputed busiest airport in the country, O’Hare more recently has competed with other large facilities across the country for the distinction, while a rejuvenated Midway became a regional hub. For decades the city has debated the issue of......
  • OHCHR (international organization)
    department of the United Nations (UN) created to aid and protect human rights. The UN General Assembly Resolution 48/141 created the OHCHR in its present form in 1993. The OHCHR works with all levels of government internationally to achieve its goals to protect human rights across the globe....
  • O’Herlihy, Dan (Irish actor)
    Irish actor (b. May 1, 1919, Wexford, Ire.—d. Feb. 17, 2005, Malibu, Calif.), earned an Academy Award nomination for his starring performance in Luis Buñuel’s film The Adventures of Robinson Crusoe (1954). O’Herlihy began his 50-year acting career at the Abbey and Gate theatres in Dublin before making his film debut in Odd Man Out (1947). He made his Holly...
  • O’Herlihy, Daniel Peter (Irish actor)
    Irish actor (b. May 1, 1919, Wexford, Ire.—d. Feb. 17, 2005, Malibu, Calif.), earned an Academy Award nomination for his starring performance in Luis Buñuel’s film The Adventures of Robinson Crusoe (1954). O’Herlihy began his 50-year acting career at the Abbey and Gate theatres in Dublin before making his film debut in Odd Man Out (1947). He made his Holly...
  • OHF (metallurgy)
    ...or 1,600° C) was high enough to permit melting steel for the first time, producing a homogeneous metal of uniform composition that he used to manufacture watch and clock springs. After 1870 the Siemens regenerative gas furnace replaced the coke-fire furnace; it produced even higher temperatures. The Siemens furnace had a number of combustion holes, each holding several crucibles, and hea...
  • O’Higgins (region, Chile)
    region, central Chile, bordered by Argentina to the east and facing the Pacific Ocean on the west. Since 1974 it has comprised the provinces of Cachapoal, Cardenal Caro, and Colchagua. It has an area of 6,327 sq mi (16,393 sq km) and was named after the nation’s first president, Bernardo O’Higgins....
  • O’Higgins, Ambrosio (Spanish officer)
    Bernardo O’Higgins was born in Chillán, a town in southern Chile, then a colony of Spain. As noted in his Certificate of Baptism, he was the illegitimate son of Ambrosio O’Higgins, a Spanish officer of Irish origin who became governor of Chile and later viceroy of Peru; his mother was Isabel Riquelme, a prominent lady of Chillán....
  • O’Higgins, Bernardo (Chilean head of state)
    South American revolutionary leader and first Chilean head of state (“supreme director,” 1817–23), who commanded the military forces that won independence from Spain....
  • O’Higgins, Kevin Christopher (Irish statesman)
    Irish statesman who attempted severe repression of the Irish Republican Army (IRA) in the years of the Irish “Troubles” following the Anglo-Irish treaty of 1921. A man of intellectual power, he was described as “a soul incapable of remorse or rest” and (by William Butler Yeats) “a great man in his pride confronting murderous men.” He was in fact murdered b...
  • O’Higgins Land (peninsula, Antarctica)
    peninsula claimed by Britain, Chile, and Argentina. It forms an 800-mile (1,300-kilometre) northward extension of Antarctica toward the southern tip of South America. The peninsula is ice-covered and mountainous, the highest point being Mount Jackson at 13,750 feet (4,190 metres). Marguerite Bay indents the west coast, and Bransfield Strait separates the peninsula from the South Shetland Islands t...
  • Ohio (United States submarine class)
    ...could launch its warheads a distance of 2,500 nautical miles. To carry 24 Trident missiles, improved versions of which could travel about 6,500 nautical miles, the U.S. Navy commissioned the first Ohio-class submarine in 1981 (see photograph). These vessels displaced 16,600 tons at the surface and were about as long as the Soviet Typhoons....
  • Ohio (state, United States)
    constituent state of the United States of America. Lake Erie lies on the north, Pennsylvania on the east, West Virginia and Kentucky on the southeast and south, and Michigan on the northwest. Its area of 41,330 square miles (107,044 square kilometres), excluding 3,457 square miles in Lake Erie, ranks only 35th in size among the states, and it is one of the smallest states west of the Appalachian M...
  • Ohio Agricultural and Mechanical College (university system, Ohio, United States)
    state university system of Ohio, U.S., consisting of a main campus in Columbus and branches in Lima, Mansfield, Marion, Newark, and the Agricultural Technical Institute in Wooster. The institute and the branches in Mansfield and Newark are primarily two-year colleges. The main campus in Columbus is a comprehensive research institution with land-grant status. It comprises some tw...
  • Ohio and Erie Canal (waterway, United States)
    ...between the Mississippi River and the Great Lakes. Laid out in 1825 by Gen. Simon Perkins, commissioner of the Ohio Canal Fund, the town was assured substantial growth by the completion of the Ohio and Erie Canal in 1827 and of the Pennsylvania and Ohio Canal in 1840, linking it with Pittsburgh. Waterpower and transportation supplied by these canals led to Akron’s early development as an...
  • Ohio buckeye (plant)
    Among the most notable is the Ohio buckeye (A. glabra), also called fetid buckeye and American horse chestnut, a tree growing up to 21 m (70 feet) in height, with twigs and leaves that yield an unpleasant odour when crushed. The digitate leaves, of five to seven leaflets, turn orange to yellow in fall....
  • Ohio Company (United States history)
    in U.S. colonial history, organization of Englishmen and Virginians, established in 1748, to promote trade with groups of American Indians and to secure English control of the Ohio River valley. Its activities in an area also claimed by France led to the outbreak of the last French and Indian War (1754). A separate organization, the Ohio Company of Associates (1786), founded Marietta, the first s...
  • Ohio Company of Associates (United States history)
    Cited for heroism as an American Revolutionary War chaplain, Cutler joined with other veterans of the war in Boston in 1786 to form the Ohio Company of Associates in order to develop the Ohio Valley. The veterans hoped to use their depreciated Continental certificates at par value for the purchase of a large tract of land....
  • Ohio, flag of (United States state flag)
    ...
  • Ohio Gang (American politician)
    in U.S. history, a group of politicians who achieved high office during the presidential administration of Warren G. Harding and who betrayed their public trust through a number of scandals. Leader of the Ohio Gang was Harry M. Daugherty, a long-time political operative who was the principal manager of Harding’s political ascendancy and who was named a...
  • Ohio Idea (United States history)
    in U.S. history, proposal first presented in the Cincinnati Enquirer in 1867 and later sponsored by Senator George H. Pendleton of Ohio to redeem American Civil War bonds in paper money instead of gold....
  • Ohio Mechanics’ Institute (college, Cincinnati, Ohio, United States)
    ...had moved to Boston, founded the Boston Mechanics’ Institute in 1826, but its reliance on lectures doomed it. Claxton tried again, founding the Boston Mechanics’ Lyceum in 1831. In Cincinnati the Ohio Mechanics’ Institute opened in 1829. In France, Baron Charles Dupin founded several institutes before 1826, beginning at La Rochelle and Nevers....
  • Ohio Players, The (American music group)
    American funk and pop band from Dayton, Ohio, that put an indelible stamp on black music from the urban Midwest in the 1970s. The principal members were Clarence (“Satch”) Satchell (b. April 14, 1940Cleveland, Ohio, U.S.—d. Dec. 31, 1995...
  • Ohio River (river, United States)
    major river artery of the east-central United States. Formed by the confluence of the Allegheny and Monongahela rivers at Pittsburgh, it flows northwest out of Pennsylvania, then in a general southwesterly direction to join the Mississippi River at Cairo, Illinois (see ), after a course of 981 miles (1,579 km). It m...
  • Ohio State League (American sports organization)
    In midseason that year the International League’s board of directors told its secretary to approve no more contracts for black players, although it did not oust the league’s five blacks. The Ohio State League also wrestled inconclusively with the colour question. It was becoming clear that the colour bar was gradually being raised. Black players were in the minor leagues for the next...
  • Ohio State University (university system, Ohio, United States)
    state university system of Ohio, U.S., consisting of a main campus in Columbus and branches in Lima, Mansfield, Marion, Newark, and the Agricultural Technical Institute in Wooster. The institute and the branches in Mansfield and Newark are primarily two-year colleges. The main campus in Columbus is a comprehensive research institution with land-grant status. It comprises some tw...
  • Ohio University (university, Athens, Ohio, United States)
    public, coeducational institution of higher learning in Athens, Ohio, U.S., about 80 miles (130 km) southeast of Columbus. It was the first institution of higher education in the Northwest Territory. The university has branches in Chillicothe, Ironton, Lancaster, St. Clairsville, and Zanesville. The main campus includes colleges of arts and sciences, business, engineering and te...
  • Ohio Wesleyan University (university, Delaware, Ohio, United States)
    ...Col. Moses Byxbe of Massachusetts settled on the east bank of the river in 1804. The town was laid out in 1808 and became a popular health resort because of its close proximity to a sulfur spring. Ohio Wesleyan University (1842) was built around the town’s Mansion House (now Elliot Hall). The Methodist Theological School in Ohio was opened in Delaware in 1960. Perkins Observatory, mainta...
  • Ōhira Masayoshi (prime minister of Japan)
    prime minister of Japan from 1978 to 1980....
  • Ohl, Russell (American scientist)
    ...in photography. These early solar cells, however, still had energy-conversion efficiencies of less than 1 percent. This impasse was finally overcome with the development of the silicon solar cell by Russell Ohl in 1941. Thirteen years later, aided by the rapid commercialization of silicon technology needed to fabricate the transistor, three other American researchers—Gerald Pearson, Dary...
  • Ohlin, Bertil (Swedish economist)
    Swedish economist and political leader who is known as the founder of the modern theory of the dynamics of trade. In 1977 he shared the Nobel Prize for Economics with James Meade....
  • Ohlin, Bertil Gotthard (Swedish economist)
    Swedish economist and political leader who is known as the founder of the modern theory of the dynamics of trade. In 1977 he shared the Nobel Prize for Economics with James Meade....
  • ohm (unit of energy measurement)
    abbreviation Ω, unit of electrical resistance in the metre-kilogram-second system, named in honour of the 19th-century German physicist Georg Simon Ohm. It is equal to the resistance of a circuit in which a potential difference of one volt produces a current of one ampere (1Ω = 1 V/A); or, the resistance in which one watt of power is dissipated when ...
  • Ohm, Georg Simon (German physicist)
    German physicist who discovered the law, named after him, which states that the current flow through a conductor is directly proportional to the potential difference (voltage) and inversely proportional to the resistance....
  • ohm-metre (unit of measurement)
    ...In the metre-kilogram-second (mks) system, the ratio of area in square metres to length in metres simplifies to just metres. Thus, in the metre-kilogram-second system, the unit of resistivity is ohm-metre. If lengths are measured in centimetres, resistivity may be expressed in units of ohm-centimetre....
  • ohmic contact (electronics)
    ...circuits. Metal-semiconductor contacts can also be nonrectifying; i.e., the contact has a negligible resistance regardless of the polarity of the applied voltage. Such a contact is called an ohmic contact. All semiconductor devices as well as integrated circuits need ohmic contacts to make connections to other devices in an electronic system....
  • ohmic heating
    An alternate method for heating foods, called ohmic heating, passes a low-frequency electric current of 50 to 60 hertz directly through the food. A liquid food containing solids, such as diced fruit, is pumped through a pipe surrounded by electrodes. The product is heated as long as the electrical conductivity of the food is uniform throughout the entire volume. This uniform rate of heating......
  • ohmmeter (instrument)
    instrument for measuring electrical resistance, which is expressed in ohms. In the simplest ohmmeters, the resistance to be measured may be connected to the instrument in parallel or in series. If in parallel (parallel ohmmeter), the instrument will draw more current as resistance increases. If in series (series ohmmeter), current will decrease as resistance rises. Ratio meters measure the ratio ...
  • Ohm’s law (physics)
    in electricity, experimentally discovered relationship that the amount of steady current through a large number of materials is directly proportional to the potential difference, or voltage, across the materials. Thus, if the voltage V (in units of volts) between two ends of a wire made from one of these materials is tripled, the current I (ampe...
  • Ohm’s law of electrical resistance (physics)
    in electricity, experimentally discovered relationship that the amount of steady current through a large number of materials is directly proportional to the potential difference, or voltage, across the materials. Thus, if the voltage V (in units of volts) between two ends of a wire made from one of these materials is tripled, the current I (ampe...
  • Ohm’s law of hearing (physics)
    ...Ohm first suggested that the ear is sensitive to these spectral components; his idea that the ear is sensitive to the amplitudes but not the phases of the harmonics of a complex tone is known as Ohm’s law of hearing (distinguishing it from the more famous Ohm’s law of electrical resistance)....
  • Ohno Taiichi (Japanese businessman)
    Japanese production-control expert for the Toyota Motor Co. whose just-in-time system (kanban) revolutionized manufacturing methods....
  • Ohře River (river, Europe)
    tributary of the Elbe River, rising in the Fichtel Mountains (Fichtelgebirge) of Germany and flowing generally east and northeastward into the Czech Republic past Cheb, Karlovy Vary, Žatec, and Louny until it reaches the Elbe (Labe) River opposite Litoměřice. The river is 196 miles (316 km) long, and it receives the Teplá and Blšanka rivers from the south and the...
  • Ohrid (Macedonia)
    town, Macedonia, on the northeastern shore of Lake Ohrid (Ohridsko Jezero). The chief resort of Macedonia, Ohrid is linked by rail, road, and air to Skopje. Agriculture, fishing, and tourism provide a livelihood for the population....
  • Ohrid, Lake (lake, Albania-Macedonia)
    lake on the Macedonia-Albania border, southeastern Europe. It has an area of 134 square miles (347 square km). At 938 feet (286 m), it is the deepest lake in the Balkans. It is connected by underground channels to Lake Prespa to the southeast. Lake Ohrid is known for its beauty and its fishing, and there are several beaches. Interesting historic buildings are found in the towns that lie along its ...
  • Ohridsko Jezero (lake, Albania-Macedonia)
    lake on the Macedonia-Albania border, southeastern Europe. It has an area of 134 square miles (347 square km). At 938 feet (286 m), it is the deepest lake in the Balkans. It is connected by underground channels to Lake Prespa to the southeast. Lake Ohrid is known for its beauty and its fishing, and there are several beaches. Interesting historic buildings are found in the towns that lie along its ...
  • Ohrmazd (Zoroastrian deity)
    supreme god in ancient Iranian religion, especially in the religious system of the Iranian prophet Zoroaster (7th century–6th century bc). Ahura Mazdā was worshiped by the Persian king Darius I (reigned 522 bc–486 bc) and his successors as the greatest of all gods and protector of the just king....
  • Ohrmuschelstil (decorative art)
    a 17th-century ornamental style based on parts of the human anatomy. It was invented in the early 17th century by Dutch silversmiths and brothers Paulus and Adam van Vianen. Paulus was inspired by anatomy lectures he attended in Prague, and both he and Adam became known for the style. The auricular style was adopted by other cabinetmakers and carvers in the Low Countries and Germany....
  • Oiapoque, Rio (river, South America)
    river that forms the border between French Guiana and the Brazilian state of Amapá. It rises in the Tumuc-Humac Mountains and flows northeast for 311 miles (500 km) to empty into the Atlantic near Cape Orange. The country through which it passes is thinly populated and is mostly covered by an unbroken tropical rain forest. Near the river’s mouth are the ports of Saint-Georges, French...
  • OIC (United States government)
    On Sept. 9, 1998, the report of the Office of the Independent Counsel (OIC) was presented to the U.S. Congress. The culmination of a four-year, $40 million investigation by Independent Counsel Kenneth Starr (see BIOGRAPHIES) into the conduct of U.S. Pres. Bill Clinton (see BIOGRAPHIES), the report concluded t...
  • OIC (Islamic organization)
    an Islamic organization established in Jeddah, Saudi Arabia, in May 1971, following summits by Muslim heads of state and government in 1969 and by Muslim foreign ministers in 1970. The membership includes Afghanistan, Algeria, Bahrain, Bangladesh, Benin, Brunei, Burkina Faso, Cameroon, Chad, Comoros, Djibouti, Egypt, Gabon, The Gambia, Guinea, Guinea-Bissau, Indonesia, Iran, Iraq, Jordan, Kuwait, ...
  • Oidemia nigra (bird)
    ...scoter (M. deglandi, or fusca) is nearly circumpolar in distribution north of the Equator, as is the black, or common, scoter (M., or sometimes Oidemia, nigra). The black scoter is the least abundant in the New World. All three species of scoter feed mainly on marine animals such as clams; only about 10 percent of their diet is plant material. The three species......
  • oidium (biology)
    in fungi (kingdom Fungi), a single-celled asexual spore (arthrospore) produced by fragmentation of fungal filaments (hyphae) in lower fungi; the asexual stage of Erysiphaceae (powdery mildew fungi); or, in Basidiomycota, both an asexual spore (microconidium) and a male cell (spermatium)....
  • oidor (Spanish judge)
    ...to administer royal justice; also, one of the most important governmental institutions of Spanish colonial America. In Spain the ordinary judges of audiencias in civil cases were called oidores and, for criminal cases, alcaldes de crimen. The presiding officer of the audiencia was called gobernador, or regente. From the reign of Philip II (1556–98),......
  • oie, l’ (board game)
    ancient French board game, said to have been derived from the Greeks, which was popular in Europe at the end of the Middle Ages....
  • Oignies, Hugo d’ (French metalworker)
    The growing naturalism of the 13th century is notable in the work of Nicholas’ follower Hugo d’Oignies, whose reliquary for the rib of St. Peter at Namur (1228) foreshadows the partly crystal reliquaries in which the freestanding relic is exposed to the view of the faithful; it is decorated with Hugo’s particularly fine filigree and enriched by naturalistic cutout leaves and l...
  • oikonomoi (Hellenistic official)
    ...until the 1st century of the Common era. The archives were managed both in the capital and in provincial cities by an official called a bibliophylax. There were many financial officials (oikonomoi); some of them oversaw royal possessions, and others managed local taxes and other economic matters. The legal system in the Seleucid empire is not well understood, but presumably both.....
  • oikonomos (Hellenistic official)
    ...until the 1st century of the Common era. The archives were managed both in the capital and in provincial cities by an official called a bibliophylax. There were many financial officials (oikonomoi); some of them oversaw royal possessions, and others managed local taxes and other economic matters. The legal system in the Seleucid empire is not well understood, but presumably both.....
  • oikoumene (religion)
    The ideology that had prevailed since Constantine (4th century) and Justinian I (6th century)—according to which there was to be only one universal Christian society, the oikoumenē, led jointly by the empire and the church—was still the ideology of the Byzantine emperors. The authority of the patriarch of Constantinople was motivated in a formal fashion by the fact that...
  • oil (chemical compound)
    any greasy substance that is liquid at room temperature and insoluble in water. It may be fixed, or nonvolatile, oil; essential oil; or mineral oil (see petroleum)....
  • oil
    complex mixture of hydrocarbons that occur in the Earth in liquid, gaseous, or solid forms. The term is often restricted to the liquid form, commonly called crude oil, but as a technical term it also includes natural gas and the viscous or solid form known as bitumen. The liquid and gaseous phases of petroleum constitute the most important of the primary fossil fuels....
  • oil (biochemistry)
    any of a diverse group of organic compounds including fats, oils, hormones, and certain components of membranes that are grouped together because they do not interact appreciably with water. One type of lipid, the triglycerides, is sequestered as fat in adipose cells, which serve as the energy-storage depot for organisms and also provide thermal insulation. So...
  • oil beetle (insect)
    The members of the subfamily Meloinae are sometimes known as oil beetles. They do not have hindwings as do most blister beetles, nor do their wing covers meet in the middle of the back; rather, the covers are much shorter and overlap. Oil beetles secrete an oily substance that protects them from predators because of its bad taste. In some species the forcepslike antennae of the male are used to......
  • oil burner
    heating device in which fuel oil is mixed with air under controlled conditions. In most burners oil is supplied under pressure to an atomizing nozzle to produce a fine spray, to which air is added by a motor-driven fan. As the cone-shaped spray emerges from the nozzle, ignition is usually supplied by an electric spark to start the burner. Starting and shut-off are normally controlled by thermosta...
  • oil cake (chemistry)
    coarse residue obtained after oil is removed from various oilseeds, rich in protein and minerals and valuable as poultry and other animal feed. It may be broken up and sold or be ground into oil meal. Oil cakes from certain seeds such as castor beans and tung nuts are toxic and are used as fertilizers rather than feed....
  • oil cell (plant anatomy)
    ...sometimes even within a single family (e.g., Winteraceae). There is, however, no clear way to discern the primitive from the advanced types of stomata. Most Magnoliidae contain ethereal oil cells, commonly with isoquinoline alkaloids, in their leaves and often in other aerial parts as well. Such ethereal oil cells are not found in other subclasses. It has been suggested that they......
  • Oil City (Pennsylvania, United States)
    city, Venango county, northwestern Pennsylvania, U.S., on a bend of the Allegheny River at the mouth of Oil Creek, 70 miles (113 km) north of Pittsburgh. Founded in 1860 on the site of a Seneca Indian village, it burgeoned as an oil centre after the drilling of the world’s first oil well (August 27, 1859) at ...
  • oil, essential (plant substance)
    highly volatile substance isolated by a physical process from an odoriferous plant of a single botanical species. The oil bears the name of the plant from which it is derived; for example, rose oil or peppermint oil. Such oils were called essential because they were thought to represent the very essence of odour and flavour....
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