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  • Omar, Dullah (South African lawyer)
    South African human rights lawyer and politician (b. May 26, 1934, Observatory, S.Af.—d. March 13, 2004, Cape Town, S.Af.), was an antiapartheid activist who became minister of justice (1994–99) in Pres. Nelson Mandela’s postapartheid administration. During his tenure Omar was responsible for dismantling the legal structure of apartheid, setting up the Truth and Reconciliation...
  • Omar Khayyam (Persian poet and astronomer)
    Persian mathematician, astronomer, and poet, renowned in his own country and time for his scientific achievements but chiefly known to English-speaking readers through the translation of a collection of his robāʿīyāt (“quatrains”) in The Rubáiyát of Omar Khayyám (1859), by the English ...
  • Omar, Mosque of (monument, Jerusalem)
    shrine in Jerusalem that is the oldest extant Islamic monument. The rock over which the shrine was built is sacred to both Muslims and Jews. The Prophet Muhammad, founder of Islam, is traditionally believed to have ascended into heaven from the site. In Jewish tradition, it is here that Abraham, the progenitor and first patriarch of the Hebrew people, is said to have prepared to sacrifice his son ...
  • Omarr, Sydney (American astrologer)
    American astrologer (b. Aug. 5, 1926, Philadelphia, Pa.—d. Jan. 2, 2003, Santa Monica, Calif.), took up his profession at the age of 15 and became probably the most widely read horoscope writer in the world. He wrote 13 books a year, one for each sign of the zodiac and one covering all 12 signs; his columns were published in more than 200 newspapers; and he served as consultant to a number ...
  • omasum (anatomy)
    In the most advanced ruminants, the much enlarged stomach consists of four parts. These include the large rumen (or paunch), the reticulum, the omasum (psalterium or manyplies)—which are all believed to be derived from the esophagus—and the abomasum (or reed), which corresponds to the stomach of other mammals. The omasum is almost absent in chevrotains. Camels have a three-chambered....
  • Omayyad dynasty (Islamic history)
    first great Muslim dynasty to rule the Empire of the Caliphate (ad 661–750), sometimes referred to as the Arab kingdom (reflecting traditional Muslim disapproval of the secular nature of the Umayyad state). The Umayyads, headed by Abū Sufyān, were a largely merchant family of the Quraysh tribe centred at Mecca. They had initi...
  • OMB (United States government)
    Since 1921 the budget of the United States has been the responsibility of the president. It is prepared under his direct authority by the Office of Management and Budget (OMB). The process begins when the various departments and agencies prepare their appropriation requests, based on expenditures required under existing law and those estimated under new legislation to be proposed by the......
  • Ombédé, Philippe Louis (Cameroonian author)
    African novelist, poet, playwright, and journalist. The Cameroon Tribune called him “one of the most influential personalities in the new wave of creative writing in Cameroon.”...
  • Ombi Islands (islands, Indonesia)
    group of the northern Moluccas, Maluku Utara (North Moluccas) provinsi (province), Indonesia. They lie south of Halmahera Island, north of Ceram Island, and east of the Sula Islands. The principal island of the group is Obi Island, 52 miles (84 km) long and 28 miles (47 km) wide, which contains the only major village, Laiwui, located on the northeastern coas...
  • Ombos (ancient city, Egypt)
    A short distance south-southwest of modern Kawm Umbū (Arabic: “Hill of Umbū”) lies ancient Ombos. It is known for its unique double temple of the Ptolemaic and Roman periods, which is dedicated to Sebek (Suchos), the crocodile god, and to Horus, the falcon-headed god. Parts of the temple’s pylon and court have been eroded away by the river. Ombos probably owed it...
  • ombre (card game)
    Anglicized version of the classic Spanish card game originally called hombre (meaning “man”) and now known as tresillo in Spain and South America....
  • ombres chinoises (puppet show)
    (French: “Chinese shadows”), European version of the Chinese shadow-puppet show, introduced in Europe in the mid-18th century by returning travelers. Soon adopted by French and English showmen, the form gained prominence in the shows of the French puppeteer Dominique Séraphin, who presented the first popular ombres chinoises in Paris in 1776. In 1781 he moved his show ...
  • ombu (plant)
    The ombu (Phytolacca dioica) is a remarkable South American relative of the pokeweed (P. americana). A tree capable of attaining heights of 20 metres (65 feet) and a spread of 30 metres (100 feet), it has a wide trunk; the branches contain as much as 80 percent water and very little wood tissue. From its base radiates a circle of rootlike outgrowths wide enough for......
  • ombudsman (government overseer)
    legislative commissioner for investigating citizens’ complaints of bureaucratic abuse. The office originated in Sweden in 1809–10 and has been copied in various forms in Scandinavia, New Zealand, the United Kingdom, Germany, and Israel and in certain states in the United States and Australia and in provinces in Canada....
  • Omdurman (The Sudan)
    one of the Three Towns (with Khartoum and Khartoum North), east-central Sudan. Situated on the bank of the main Nile River just below the confluence of the Blue and White Niles, Omdurman was an insignificant riverine village until the victory of Muḥammad Aḥmad, known as al-Mahdī, over the British in 18...
  • Omdurman, Battle of (African history)
    (Sept. 2, 1898), decisive military engagement in which Anglo-Egyptian forces, under Major General Sir Herbert Kitchener (later Lord Kitchener), defeated the forces of the Mahdist leader ʿAbd Allāh and thereby won Sudanese territory that the Mahdists had dominated since 1881....
  • Ōme (Japan)
    city, Tokyo to (metropolis), east-central Honshu, Japan, on the Tama River. An early trade centre and post town, it was known as a weaving centre for cotton textiles. Other traditional industries included the production of lumber and woodwork. Ōme became a municipality in 1951 when it and two neighbouring villages were amalgamated. Industrial plants ...
  • O’Meara, Stephen James (American police official)
    ...by experts responsible to a public authority that would be immune to political interference. During this initial period of reform, the Boston Police Department, under the leadership of Stephen James O’Meara (1906–18), came closest to implementing that administrative ideal. O’Meara was a strong chief executive who used the power of his office to create a high standard of......
  • Omecíhuatl (Aztec deity)
    Aztec deity, “Lord of the Duality” or Lord of Life, who represented one aspect of the cosmic duality of the Aztec tradition. With his female counterpart, Omecíhuatl (“Two-Lady” or “Lady of the Duality”), Ometecuhtli resided in Omeyocan (“Two-Place” or “Double Heaven”), the 13th and highest Aztec heaven. The opposing facto...
  • Ω (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 ...
  • Omega (Christianity)
    in Christianity, the first and last letters of the Greek alphabet, used to designate the comprehensiveness of God, implying that God includes all that can be. In the New Testament Revelation to John, the term is used as the self-designation of God and of Christ. The reference in Revelation likely had a Jewish origin, based on such Old Testament passages as Isa. 44:6 (“I ...
  • Omega Centauri (astronomy)
    (catalog number NGC 5139), the brightest globular star cluster. It is located in the southern constellation Centaurus. It has a magnitude of 3.7 and is visible to the unaided eye as a faint luminous patch. Omega Centauri is about 17,000 light-years from Earth and is thus one of the nearer globular clusters. It is estimated to contain hundreds of thousands of stars; several hundred variables have ...
  • omega effect (geomagnetics)
    ...to the rotation axis). Since the conductivity is not perfect, the toroidal loop may diffuse through the fluid, disconnecting itself from the original poloidal field (B). This process is called the omega effect because it depends on the rotational velocity of the fluid....
  • Omega Workshops (arts collective)
    In 1913, following a precedent that had been set by William Morris and the Arts and Crafts Movement, Fry organized a group of young artists into a collective called the Omega Workshops. The goal of the collective was to infuse the innovative aesthetic of Post-Impressionism into the design of everyday functional objects (such as drapery, furniture, and china). The bright colour and ornamental......
  • Ω- particle (subatomic particle)
    ...could be seen to fit into a decuplet, or group of 10, although at the time the classification was introduced, the 10th member of the group, the particle known as the Ω− (or omega-minus), had not yet been observed. Its discovery early in 1964, at the Brookhaven National Laboratory in Upton, New York, confirmed the validity of the SU(3) symmetry of the hadrons....
  • omega-3 fatty acid (chemical compound)
    The two types of polyunsaturated fatty acids found in foods are omega-3 fatty acids and omega-6 fatty acids. Linoleic acid, the primary omega-6 fatty acid in most diets, is widespread in foods; the major source is vegetable oils such as sunflower, safflower, and corn oils. Low cardiovascular disease rates in Eskimo populations eating traditional diets high in omega-3 fatty acids initially......
  • omega-6 fatty acid (chemical compound)
    ...each chain having an even number of carbon atoms. Of particular importance for humans are the 18-carbon polyunsaturated fatty acids alpha-linolenic acid (an omega-3 fatty acid) and linoleic acid (an omega-6 fatty acid); these are known as essential fatty acids because they are required in small amounts in the diet. The omega designations (also referred to as n-3 and n-6) indicate the location o...
  • ω-chloroacetophenone (tear gas)
    ...liquids or solids that can be finely dispersed in the air through the use of sprays, fog generators, or grenades and shells. The two most commonly used tear gases are ω-chloroacetophenone, or CN, and o-chlorobenzylidenemalononitrile, or CS. CN is the principal component of the aerosol agent Mace and is widely used in riot control. It affects chiefly the eyes. CS is a stronger......
  • omega-chloroacetophenone (tear gas)
    ...liquids or solids that can be finely dispersed in the air through the use of sprays, fog generators, or grenades and shells. The two most commonly used tear gases are ω-chloroacetophenone, or CN, and o-chlorobenzylidenemalononitrile, or CS. CN is the principal component of the aerosol agent Mace and is widely used in riot control. It affects chiefly the eyes. CS is a stronger......
  • omega-consistency (logic)
    ...of a formal system based on axioms. In 1931 Gödel made fundamental discoveries in these areas for the most interesting formal systems. In particular, he discovered that, if such a system is ω-consistent—i.e., devoid of contradiction in a sense to be explained below—then it is not complete and that, if a system is consistent, then the statement of its......
  • omega-minus particle (subatomic particle)
    ...could be seen to fit into a decuplet, or group of 10, although at the time the classification was introduced, the 10th member of the group, the particle known as the Ω− (or omega-minus), had not yet been observed. Its discovery early in 1964, at the Brookhaven National Laboratory in Upton, New York, confirmed the validity of the SU(3) symmetry of the hadrons....
  • omegatron (instrument)
    ...and magnetic fields so that ions can be held in stable orbits for a period of time long enough to perform useful measurements on them. Two forms of mass spectrometers are derived from this idea, the omegatron and the Fourier-transform spectrometer. Both make use of the cyclotron principle (see particle accelerator: Cyclotrons), in which positive ions produced by a beam of electrons flowing alon...
  • Omegna, Roberto (Italian filmmaker)
    motion picture cameraman, director, and producer of documentaries, one of the pioneers of the Italian cinema. His thorough research and filmmaking skills place him in the forefront of early documentarians....
  • omen (occultism)
    observed phenomenon that is interpreted as signifying good or bad fortune. In ancient times omens were numerous and varied and included, for instance, lightning, cloud movements, the flight of birds, and the paths of certain sacred animals. Within each type of sign were minor subdivisions, such as the different kinds of bird in flight or the direction of flight in relation to the observer, each o...
  • Omen, The (film by Donner [1976])
    ...for All the President’s MenCinematography: Haskell Wexler for Bound for GloryArt Direction: George Jenkins for All the President’s MenOriginal Score: Jerry Goldsmith for The OmenOriginal Score and Its Adaptation or Adaptation Score: Leonard Rosenman for Bound For GloryOriginal Song: “Evergreen (Love Theme from A Star Is Born)” from ...
  • Omensetter’s Luck (work by Gass)
    Gass called his fiction works “experimental constructions,” and each of his books contains stylistic innovations. His first novel, Omensetter’s Luck (1966), is about a man whose purity and good fortune are tainted when he is maliciously and falsely connected to a mysterious death. By piecing together various viewpoints, Gass creates levels of insight into character and....
  • omentum (anatomy)
    ...membrane in the abdominal cavity that connects and supports internal organs. It is composed of many folds that pass between or around the various organs. Two folds are of primary importance: the omentum, which hangs in front of the stomach and intestine; and the mesentery, which attaches the small intestine and much of the large intestine to the posterior abdominal cavity....
  • Ömer (Ottoman poet)
    one of the greatest classical Ottoman poets and one of the most famous satirists and panegyrists in Ottoman Turkish literature....
  • ʿOmer Counting, 33rd Day of the (Jewish holiday)
    a minor Jewish observance falling on the 33rd day in the period of the counting of the ʿomer (“barley sheaves”); on this day semimourning ceases and weddings are allowed. The origin of the festival is obscure. Among many traditions, one has it that manna first fell from heaven on this day; another tradition claims that a plague that raged among the followers of Rabbi Ak...
  • Ömer Seyfeddin (Turkish author)
    short-story writer who is considered to be one of the greatest modern Turkish authors....
  • Omer Seyfettin (Turkish author)
    short-story writer who is considered to be one of the greatest modern Turkish authors....
  • Omer-paša Latas (ruler of Bosnia)
    However, two Bosnian governors succeeded in forcing through some of the sultan’s reforms and curbing local resistance. The first of these, Omer-paša Latas, crushed a major rebellion in 1850–51 and revoked the separate status of Herzegovina. The second, Topal Osman-paša, introduced a new method of military conscription in 1865 and a completely new administrative system i...
  • omertà (Mafia code of honor)
    ...so despotic that they alienated the island’s inhabitants and made tolerable the Mafia’s peculiar system of private justice, which was regulated by a complicated moral code. This code was based on omertà—i.e., the obligation never, under any circumstances, to apply for justice to the legal authorities and never to assist in any way in the detection of cr...
  • Ometecuhtli (Aztec deity)
    Aztec deity, “Lord of the Duality” or Lord of Life, who represented one aspect of the cosmic duality of the Aztec tradition. With his female counterpart, Omecíhuatl (“Two-Lady” or “Lady of the Duality”), Ometecuhtli resided in Omeyocan (“Two-Place” or “Double Heaven”), the 13th and hi...
  • Ometepe (volcano, Nicaragua)
    one of two volcanic cones (the other is Madera) forming Ometepe Island in Lake Nicaragua, southwestern Nicaragua. Also known as Ometepe, it rises to 5,282 ft (1,610 m) and comprises the northern half of the island. Concepción is one of the country’s most active volcanoes and has frequent eruptions. Its first recorded activity was in 1883. ...
  • Ometepe Island (island, Nicaragua)
    island in southwestern Nicaragua, the largest island in Lake Nicaragua. Ometepe actually consists of two islands joined by a narrow isthmus 2 miles (3 km) in length. Their combined area is about 150 square miles (400 square km). The larger, northern one is 12 miles (19 km) from east to west and 10 miles (16 km) from north to south; from it the cone of active Concepci...
  • omi (Japanese title)
    ...thus headed by a hereditary ruler, while its members were drawn from the group of powerful clan leaders awarded kabane (titles). The two major titles appear to have been muraji and omi, held only by clan leaders of powerful communities serving in the area of the Yamato court. Lower-ranking titles were awarded to leaders of smaller, distant clans who nonetheless swore......
  • Omicron Ceti (star)
    first variable star (apart from novae) to be discovered, lying in the southern constellation Cetus, and the prototype of a class known as long-period variables, or Mira stars. There is some evidence that ancient Babylonian astronomers noticed its variable character. In a systematic study in 1638, a Dutch astronomer, Phocylides Holwarda, found that the star disappeared and reappeared in a varying c...
  • omicron-chlorobenzylidenemalononitrile (tear gas)
    ...air through the use of sprays, fog generators, or grenades and shells. The two most commonly used tear gases are ω-chloroacetophenone, or CN, and o-chlorobenzylidenemalononitrile, or CS. CN is the principal component of the aerosol agent Mace and is widely used in riot control. It affects chiefly the eyes. CS is a stronger irritant that causes burning sensations in the......
  • Omidyar, Pierre (American entrepreneur)
    global online auction and trading company launched by American entrepreneur Pierre Omidyar in 1995. eBay was one of the first companies to create and market an Internet Web site to match buyers and sellers of goods and services. The company, which caters to individual sellers and small businesses, is a market leader in e-commerce worldwide. eBay is headquartered in San Jose, Calif....
  • omina (ancient warning)
    ...in the sublunar world. The theoretical basis for this assumption lies historically in Hellenistic philosophy and radically distinguishes astrology from the celestial omina (“omens”) that were first categorized and cataloged in ancient Mesopotamia. Originally, astrologers presupposed a geocentric universe in which the “planets”......
  • Omina Isaac Opera (work by Israeli)
    ...into Latin in 1087 by the monk Constantine, who claimed to have written them himself. Not until 1515 was their true authorship uncovered, and the works were republished in Lyon under the title Omnia Isaac Opera (“All of Isaac’s Works”); the editor, however, mistakenly included the writings of other medical scholars as well. Israeli’s scientific works include s...
  • omission solid solution (chemistry)
    The least common type of solid solution is omission solid solution, in which a crystal contains one or more atomic sites that are not completely filled. The best-known example is exhibited by pyrrhotite (Fe1 - xS). In this mineral, each iron atom is surrounded by six neighbouring sulfur atoms. If every iron site in pyrrhotite was occupied by ferrous iron, its formula would be......
  • Ōmiya (Japan)
    Ōmiya, formerly the prefectural capital and now the northern portion of Saitama city, and Urawa, the southern part of the new city, were roughly equal in size at the time of the merger. Both had been post towns on the Nakasendō highway between Ōsaka and Edo (Tokyo) during the Tokugawa period (1603–1867), and both grew rapidly in the 20th century, especially after World....
  • Omkar temple (temple, India)
    ...central India. It lies along the Narmada River southeast of Indore. Godarpura has noted Śaivite, Vaiṣṇavite, and Jaina temples, mostly of the 14th and 18th centuries. The Omkar temple, on an island in the river, contains one of the 12 great Śiva (Shiva) phallic symbols, or lingas; another linga stands outside the Gaurī Somnāth temple. The temples on......
  • Omkarji (pilgrimage site, India)
    pilgrimage centre, western Madhya Pradesh state, central India. It lies along the Narmada River southeast of Indore. Godarpura has noted Śaivite, Vaiṣṇavite, and Jaina temples, mostly of the 14th and 18th centuries. The Omkar temple, on an island in the river, contains one of the 12 great Śiva (Shiva) phallic symbols, or lingas; another linga stands outside the Gaur...
  • OMM (Mozambican organization)
    ...behind to grow cash crops as well as crops for domestic consumption. Although women produced a significant portion of the agricultural products, they did not receive equal pay and rights. The Organization of Mozambican Women (Organização da Mulher Moçambicana; OMM) was founded by Frelimo in 1973 to mobilize women around issues of interest to them. After independence......
  • ommatidia (anatomy)
    ...rays from a small area of the field of view fall on a single facet and are concentrated upon the rhabdom of the retinula cells below. Since each point of light differs in brightness, all the ommatidia that form the retina receive a crude mosaic of the field of view. Unlike the image in a camera or in human eyes, the mosaic image in the compound eye is not inverted but erect. The fineness......
  • ommatidium (anatomy)
    ...rays from a small area of the field of view fall on a single facet and are concentrated upon the rhabdom of the retinula cells below. Since each point of light differs in brightness, all the ommatidia that form the retina receive a crude mosaic of the field of view. Unlike the image in a camera or in human eyes, the mosaic image in the compound eye is not inverted but erect. The fineness......
  • Ommatophoca rossi (mammal)
    (Ommatophoca rossi), Antarctic seal of the family Phocidae. It has a short face, very large eyes, and coarse fur that is greenish gray above with yellowish stripes on the sides and paler below. Length in both sexes is to about 2.3 metres (7.6 feet) and weight is about 150–215 kilograms (330–470 pounds). The Ross seal feeds on cephalopods and some fish and plankton and is usua...
  • ommatophore (mollusk anatomy)
    ...bilaterally symmetrical, bearing one or two pairs of tentacles, often with accessory palps, and the mouth in the middle of the ventral margin. In stylommatophoran land snails the upper tentacles, or ommatophores, are invaginable (capable of being rolled in), and the eyes are borne at the tips. In freshwater basommatophorans and most prosobranchs the eyes are located at the base of the tentacles...
  • Ommelanden (district, The Netherlands)
    The early history of the province is chiefly one of almost continuous conflict between the town of Groningen and the surrounding districts known as the Ommelanden. Although Groningen acquired a dominant position in the region, the disputes persisted; the Ommelanden subscribed to the Union of Utrecht (1579) and the revolt against Spain, while the town of Groningen remained loyal to the Spanish......
  • ommochrome (biological pigment)
    any of a group of biological pigments (biochromes) conspicuous in the eyes of insects and crustaceans as well as in the changeable chromatophores (pigment-containing cells) in the skin of cephalopods. Although ommochromes, which are derived from the breakdown of the amino acid tryptophan, are responsible for the colours of insect eyes, they are not known to be involved directly...
  • ommyō-ji (Japanese religion)
    ...in the temples, and among the people. Records from the early 7th century contain traces of Taoism, which was appreciated chiefly for its magical claims. The “masters of Yin and Yang” (ommyō-ji), a caste of diviners learned in the I Ching, Chinese astrology, and occult sciences who assumed importance at court in the Heian period (8th–12th century), proba...
  • Omnibook (American magazine)
    ...of scientific and technical matter. One that tried a new formula, based on timeliness and a liberal slant, was Reader’s Scope (1943–48). The most successful book digest was probably Omnibook (1938–57), each issue of which contained abridgments of several popular works of fiction and nonfiction. The digests originally carried no advertising, but after World War...
  • omnibus (vehicle)
    any of a class of large, self-propelled, wheeled vehicles that are designed to carry passengers, generally on a fixed route. They were developed at the beginning of the 20th century to compete with streetcars by providing greater route flexibility. The bus was a natural outgrowth of the horse-driven coach. Today buses are defined as vehicles that accommodate more than 10 passeng...
  • Omnibus (television show)
    ...Man’s America (1952) and Talk About America (1968). From 1956 to 1961 Cooke hosted and narrated the weekly television “magazine” Omnibus, which won numerous broadcasting awards....
  • omnibus hearts (card game)
    A popular four-hand variant is omnibus hearts, in which capturing the jack of diamonds (sometimes the 10 of diamonds) counts for minus 10 points. Although four players make for an ideal game, other numbers of players are possible by removing enough cards (such as black 2s) to even out the deal and by adjusting the passes (usually by eliminating the cross-pass)....
  • omnidirectional antenna (electronics)
    ...used to convert a time-varying electric current into an electromagnetic wave or field, which freely propagates through a nonconducting medium such as air or space. In a broadcast radio channel, an omnidirectional antenna radiates a transmitted signal over a wide service area. In a point-to-point radio channel, a directional transmitting antenna is used to focus the wave into a narrow beam,......
  • omnidirectional radiation (physics)
    Spectroscopic evidence that the universe was expanding was followed by the discovery in 1965 of a low level of isotropic microwave radiation by the American scientists Arno A. Penzias and Robert W. Wilson. The measured spectrum is identical to the radiation distribution expected from a blackbody, a surface that can absorb all the radiation incident on......
  • Omnipen (drug)
    drug used in the treatment of various infections, including otitis media (middle ear infection), sinusitis, and acute bacterial cystitis. Ampicillin (or alpha-aminobenzylpenicillin) is a semisynthetic penicillin, one of the first such antibiotics developed. Similar in action to penicillin G but more effe...
  • omnipotence (theology)
    ...deity may differ from culture to culture, a specific and pervasive structure of this type of deity can be discerned. The following characteristics tend to be common: (1) he is all wise and all powerful. The world comes into being because of his wisdom, and he is able to actualize the world because of his power. (2) The deity exists alone prior to the creation of the world. There is no......
  • Omnium sollicitundium (papal bull)
    ...Sardinia, and Naples in matters of patronage, the right of nomination to vacant sees, and secular jurisdiction over ecclesiastical changes. In his bulls Ex quo singulari (1742) and Omnium sollicitudinum (1744), he prohibited certain traditional practices that the Jesuits had allowed converts to retain in China and India. This ban set back the winning of converts in Asia and......
  • omnivore (biology)
    animal with wide food preferences, which can eat both plant and animal matter. Many small birds and mammals are omnivorous; deer mice and mockingbirds have diets that at different times may include a preponderance of insects or berries. Many animals generally considered carnivores are actually omnivorous, among them the red fox, which enjoys fruits and berries, and the snapping turtle, one-third o...
  • Omo (anthropological and archaeological site, Ethiopia)
    site of paleoanthropological excavations along the southern part of the Omo River in southwestern Ethiopia. Hominin (of human lineage) fossils unearthed there between 1967 and 1974 consist of about 200 teeth, four jaws, a partial skeleton, parts of two skulls, and a leg bone. The various layers have yielded remains from a broad and critical span of time in ...
  • Omo National Park (park, Ethiopia)
    site of paleoanthropological excavations along the southern part of the Omo River in southwestern Ethiopia. Hominin (of human lineage) fossils unearthed there between 1967 and 1974 consist of about 200 teeth, four jaws, a partial skeleton, parts of two skulls, and a leg bone. The various layers have yielded remains from a broad and critical span of time in ......
  • Omo remains (paleontology)
    site of paleoanthropological excavations along the southern part of the Omo River in southwestern Ethiopia. Hominin (of human lineage) fossils unearthed there between 1967 and 1974 consist of about 200 teeth, four jaws, a partial skeleton, parts of two skulls, and a leg bone. The various layers have yielded remains from a broad and critical span of time in human evolution. Moreover, the......
  • Omo River (river, Ethiopia)
    ...and the Baro rivers. All three rivers flow west to the White Nile in The Sudan. The second system is the Rift Valley internal drainage system, composed of the Awash River, the Lakes Region, and the Omo River. The Awash flows northeast to the Denakil Plain before it dissipates into a series of swamps and Lake Abe at the border with Djibouti. The Lakes Region is a self-contained drainage basin,.....
  • Omok language
    ...the estuary of the Indigirka River; and Kolyma, or Forest, Yukaghir (also called Southern Yukaghir) along the bend of the Kolyma River. Extinct earlier dialects or languages related to Yukaghir are Omok and Chuvan (Chuvantsy); these were spoken south and southwest of the current Yukaghir area. Nivkh has about 1,000 speakers, roughly half of whom live in the estuary of the Amur River and the......
  • Omomyidae
    ...evolved; one genus, Europolemur, is even known to have a had a toilet claw, the large claw that in modern species replaces a nail on the second toe of the foot. Representatives of the Omomyidae have been found in North America, Europe, Egypt, and Asia....
  • Omoo (novel by Melville)
    ...had been unproductive. He joined a mutiny that landed the mutineers in a Tahitian jail, from which he escaped without difficulty. On these events and their sequel, Melville based his second book, Omoo (1847). Lighthearted in tone, with the mutiny shown as something of a farce, it describes Melville’s travels through the islands, accompanied by Long Ghost, formerly the ship’...
  • omophorion (ecclesiastical garb)
    The equivalent vestment in the Eastern churches is the omophorion, a long, white silk or velvet embroidered scarf, worn by bishops celebrating the holy liturgy....
  • Omortag (khan of Bulgaria)
    ...victim to assassination, but before his death events beyond his control had improved the empire’s situation. Krum died suddenly in 814 as he was preparing an attack upon Constantinople, and his son, Omortag, arranged a peace with the Byzantine Empire in order to protect the western frontiers of his Bulgar empire against the pressures exerted by Frankish expansion under Charlemagne and hi...
  • Omote Nihon (industrial area, Japan)
    industrial region, central Japan, extending along the Tōkaidō Line (railway) between Tokyo and Nagoya, and occupying areas of Shizuoka ken (prefecture). Tōkai is neither an administrative nor a political entity. It has close economic ties with the Chūkyō Industrial Zone. The region is characterized by both coastal lowlands and the inland peaks. Traditional...
  • Omotic languages
    family of about 40 languages spoken in western Ethiopia. Although most scholars assign them to the Afro-Asiatic language phylum, this classification is subject to ongoing debate: because their speakers were for many years very little known and reside in regions that are dominated by Cushitic languages, the Omotic languages were once classifi...
  • Ōmoto (Japanese religion)
    religious movement of Japan that had a large following in the period between World War I and World War II and that served as a model for numerous other sects in that country. The teaching of Ōmoto is based on divine oracles transmitted through a peasant woman, Deguchi Nao, whose healing powers attracted an early following. Her first revelation in 1892 foretold the destruction of the world a...
  • Ōmoto-kyō (Japanese religion)
    religious movement of Japan that had a large following in the period between World War I and World War II and that served as a model for numerous other sects in that country. The teaching of Ōmoto is based on divine oracles transmitted through a peasant woman, Deguchi Nao, whose healing powers attracted an early following. Her first revelation in 1892 foretold the destruction of the world a...
  • Omotoso, Kole (Nigerian novelist)
    Nigerian novelist, playwright, and critic who wrote from a Yoruba perspective and coupled the folklore he learned as a child with his adult studies in Arabic and English. His major themes include interracial marriage, comic aspects of the Biafran-Nigerian conflict, and the human condition—as exemplified in friendship between the Yoruba and the Igbo and in relationships be...
  • omphacite (mineral)
    Omphacite is restricted in occurrence to the high-pressure and high-temperature rocks called eclogites. Eclogites represent the most deep-seated conditions of metamorphism and are characterized by an assemblage of omphacite and magnesium-rich pyrope garnet. Omphacite-bearing eclogite nodules are associated with peridotites in the kimberlite......
  • Omphalea (plant genus)
    genus of tropical shrubs or trees of the spurge family (Euphorbiaceae), comprising 15 species; 12 are native to the Americas, 3 to the Old World. O. triandra, the Jamaican cobnut, or pop nut, is native to the West Indies and cultivated in Europe. It grows to about 3.5 metres (11.5 feet) and bears yellow nuts 3.75 centimetres (1.5 inches) thick, which are edible if...
  • Omphalea diandra (plant)
    ...metres (11.5 feet) and bears yellow nuts 3.75 centimetres (1.5 inches) thick, which are edible if the poisonous embryo is removed. Juice from the fruit blackens and is used in making ink and glue. O. diandra, native to Colombia, bears edible oily seeds that are also used as hog feed. Large hunter’s nuts from O. megacarpa are a stimulating, nutritious food popular in the Wes...
  • Omphalea megacarpa (plant)
    ...is removed. Juice from the fruit blackens and is used in making ink and glue. O. diandra, native to Colombia, bears edible oily seeds that are also used as hog feed. Large hunter’s nuts from O. megacarpa are a stimulating, nutritious food popular in the West Indies....
  • Omphalea triandra (plant)
    ...the nut to its husk. This distinction was found to be misleading, and filbert became the common name for the genus in the U.S. The term cobnut is limited to a commercial variety of one species; the Jamaican cobnut has a similar flavour but is an unrelated plant of the family Euphorbiaceae. The terms hazel and hazelnut, however, are still in popular use....
  • omphalos (Greek religion)
    ...of the universe. For the ancient Greeks the grave marker (a mound of earth or a stone) was the earth altar upon which sacrifices to the dead were made and, like other earth altars, it was called the omphalos, “the navel” of the Earth—i.e., the central point from which terrestrial life originated. In Vedic India the altar was regarded as a microcosm, its parts......
  • Omri (king of Israel)
    (reigned 876–869 or c. 884–c. 872 bc), king of Israel, the father of Ahab....
  • Omsk (Russia)
    city and administrative centre of Omsk oblast (province), west-central Russia, on the Irtysh River at its junction with the Om. Omsk, founded in 1716 as a stronghold at the eastern end of the Ishim fortified line between the Tobol and the Irtysh, developed as an agricultural centre and became a city in 1804. Its military function as headquarters of the Siberian Cossacks lasted until the la...
  • Omsk (oblast, Russia)
    oblast (province), west central Russia, covering an area of 53,900 sq mi (139,700 sq km) in the basin of the middle Irtysh River. Its entire surface is an extremely flat plain, with extensive marshes and peat bogs in the north and innumerable lakes, of which Lake Tenis is the largest. Many southern lakes are saline. In the north is a dense, swampy forest, or taiga, of pine, fir, spruce, an...
  • Ōmura (Japan)
    city, Nagasaki ken (prefecture), Kyushu, Japan, facing Ōmura-wan (Ōmura Bay), on the western slopes of Tara-dake (Mt. Tara). In the 12th century it was the residence of the Ōmura daimyo and later developed as a port and post town. It became a base for trade with Portugal and a centre of Christianity in the late 16th century. The city is now an industr...
  • Ōmura Masujirō (Japanese military strategist)
    Japanese scholar and soldier popularly regarded in Japan as the founder of the modern Japanese Army....
  • Ōmura Sumitada (Japanese lord)
    ...and the acquisition of military equipment and supplies, protected Christianity. Some daimyo became Christian converts. Three Kyushu Christian lords—Ōtomo Sōrin, Arima Harunobu, and Ōmura Sumitada—even sent an embassy to Rome. Farmers also increasingly became converts, in part because of the influence of the social relief work and medical aid that accompanied.....
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