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  • ocean ranching (fishing technology)
    the rearing of fish and shellfish under artificially controlled conditions to restock the sea. See aquaculture....
  • Ocean Springs (Mississippi, United States)
    resort city, Jackson county, southeastern Mississippi, U.S., on Biloxi Bay across from Biloxi. It developed around the site of Old Biloxi, where the explorer Pierre Le Moyne d’Iberville established Fort Maurepas in 1699 for France; it was the first permanent European settlement in the lower Mississippi River valley. Its name was chang...
  • ocean sunfish (fish family)
    any of three species of oceanic fishes of the family Molidae. Molas are distinctive in appearance, with short bodies that end abruptly just behind the tall, triangular dorsal and anal fins. The fishes are also flattened from side to side and have tough skins, small mouths, and fused, beaklike teeth....
  • ocean thermal energy conversion (technology)
    Another more promising technology, known as ocean thermal energy conversion (OTEC), makes use of the temperature differential between the warm surface waters of the oceans, heated by solar radiation, and the deeper cold waters to generate power in a conventional heat engine. The difference in temperature between the surface and lower water layer can be as large as 50° C over vertical......
  • ocean wave
    There are many types of ocean waves. Waves differ from each other in size and in terms of the forces that drive them. Waves represent an oscillatory motion of seawater at regular time intervals or periods. Some may be running, or progressive, waves in which the crests propagate, while others are stationary, or standing, waves. Two of the more common types of waves, gravity waves and tides, are......
  • ocean-atmosphere interaction
    The circulation of the ocean is a key factor in air temperature distribution. Ocean currents that have a northward or southward component, such as the warm Gulf Stream in the North Atlantic or the cold Peru (Humboldt) Current off South America, effectively exchange heat between low and high latitudes. In tropical latitudes the ocean accounts for a third or more of the poleward heat transport;......
  • ocean-climate interaction
    The circulation of the ocean is a key factor in air temperature distribution. Ocean currents that have a northward or southward component, such as the warm Gulf Stream in the North Atlantic or the cold Peru (Humboldt) Current off South America, effectively exchange heat between low and high latitudes. In tropical latitudes the ocean accounts for a third or more of the poleward heat transport;......
  • “Oceana” (work by Harrington)
    English political philosopher whose major work, The Common-wealth of Oceana (1656), was a restatement of Aristotle’s theory of constitutional stability and revolution....
  • oceanarium (saltwater aquarium)
    saltwater aquarium for displaying marine animals and plants, particularly oceanic, or pelagic, fishes and mammals. It serves as a centre for public entertainment and education and scientific study. Most oceanariums are located in coastal areas. The world’s first large oceanarium, now known as Marineland, was completed in 1938 near St. Augustine, Fla., U.S....
  • Oceanarium (oceanarium, Chicago, Illinois, United States)
    ...(340,000 litres) of seawater nearly every hour and contains a wide variety of marine animals, including nurse sharks, sea turtles, moray eels, and numerous rare and colourful varieties of fish. The Oceanarium, a major addition completed in 1991, is the world’s largest indoor marine-mammal pavilion. It recreates a Pacific Northwest coastal environment and exhibits beluga whales and dolphi...
  • Oceania (region, Pacific Ocean)
    collective name for the islands scattered throughout most of the Pacific Ocean. The term, in its widest sense, embraces the entire insular region between Asia and the Americas. A more common definition excludes the Ryukyu, Kuril, and Aleutian islands and the Japan archipelago. The most popular usage delimits Oceania further by eliminating Indonesia, Taiwan, and the Philippines, because the peoples...
  • Oceanian art (visual arts)
    the visual art and architecture of native Oceania, including media such as sculpture, pottery, rock art, basketry, masks, painting, and personal decoration. In these cultures, art and architecture have often been closely connected—for example, storehouses and meetinghouses are often decorated with elaborate carvings—and so they are presented together in this discus...
  • Oceanian languages
    the visual art and architecture of native Oceania, including media such as sculpture, pottery, rock art, basketry, masks, painting, and personal decoration. In these cultures, art and architecture have often been closely connected—for example, storehouses and meetinghouses are often decorated with elaborate carvings—and so they are presented together in this discus...
  • Oceanic architecture
    the visual art and architecture of native Oceania, including media such as sculpture, pottery, rock art, basketry, masks, painting, and personal decoration. In these cultures, art and architecture have often been closely connected—for example, storehouses and meetinghouses are often decorated with elaborate carvings—and so they are presented together in this discussion....
  • Oceanic art (visual arts)
    the visual art and architecture of native Oceania, including media such as sculpture, pottery, rock art, basketry, masks, painting, and personal decoration. In these cultures, art and architecture have often been closely connected—for example, storehouses and meetinghouses are often decorated with elaborate carvings—and so they are presented together in this discus...
  • Oceanic arts
    the literary, performing, and visual arts of the Pacific Islands, including Australia, New Zealand, and Easter Island, and the general culture areas of Polynesia, Melanesia, and Micronesia. Many of the island clusters within these culture areas are separated by vast stretches of ocean, and the resultant isolation, together with the wide range of environmental conditions present,...
  • oceanic bonito (fish)
    The order includes many of the world’s most important food and game fishes, such as tunas, mackerels, bonitos, and skipjacks (family Scombridae), billfishes and marlins (Istiophoridae), swordfish (Xiphiidae), sea basses (Serranidae), and carangids (Carangidae), a large family that includes......
  • oceanic circulation
    horizontal and vertical circulation system of ocean waters produced by gravity, wind friction, and water density variation in different parts of the ocean....
  • oceanic climate (meteorology)
    The pure oceanic climate prevails in the northwest, especially in Brittany. It is characterized by its low annual temperature variation, with Brest having an average temperature in January of 43 °F (6 °C) and in July of 61 °F (16 °C); by its extreme humidity and moderate rainfall (35 inches [890 mm] of rain falling through the year), accompanied by cloudiness and haze; ...
  • oceanic crust (geology)
    Oceanic crust...
  • Oceanic dance
    the music and dance traditions of the indigenous people of Oceania, in particular of Melanesia, Micronesia, Polynesia, New Zealand, and Australia. Music and dance in Polynesia and Micronesia are audible and visual extensions of poetry, whereas in Melanesia they are aimed more at spectacular display during times of life crises and as a part of secret-society rituals. The arts of......
  • oceanic dolphin (mammal family)
    any of the toothed whales belonging to the families Delphinidae (oceanic dolphins) or Platanistidae (river dolphins). Of the 32 species of dolphins in the Delphinidae, 6 are commonly called whales, including the killer whale and the pilot whales....
  • oceanic island (geology)
    Among purely oceanic islands (i.e., those without any foundation of continental rock, usually formed as the result of volcanic action) are Iceland, the Azores, Ascension, St. Helena, Tristan da Cunha, Bouvet, and Gough, which all rise from the Mid-Atlantic Ridge; and the Canary, Madeira, and Cape Verde islands and Fernando de Noronha (near Cape São Roque), which rise from the continental......
  • Oceanic languages
    widespread, highly varied, and controversial language group of the Austronesian language family. Spoken on the islands of Oceania from New Guinea to Hawaii to Easter Island, certain of these languages share so little basic vocabulary that some scholars prefer to classify them in smaller, more cohesive groups....
  • Oceanic literature
    the traditional oral and written literatures of the indigenous people of Oceania, in particular of Melanesia, Polynesia, Micronesia, and Australia. While this article addresses the influence of Western literary forms, it does not address the adoption of purely Western styles; see also Australian literature and New Zealand literature for more on the oral tradit...
  • oceanic lithosphere (geology)
    The map of the structural features of Australia and the surrounding region shows the distribution of the main tectonic units. The primary distinction is between the plates of oceanic lithosphere, generated within the past 160 million years by seafloor spreading at the oceanic ridges, and the continental lithosphere, accumulated over the past 4 billion years. (The lithosphere is the outer rock......
  • Oceanic music
    the music and dance traditions of the indigenous people of Oceania, in particular of Melanesia, Micronesia, Polynesia, New Zealand, and Australia. Music and dance in Polynesia and Micronesia are audible and visual extensions of poetry, whereas in Melanesia they are aimed more at spectacular display during times of life crises and as a part of secret-society rituals. The arts of music and dance are...
  • Oceanic people
    The long-term history of the Oceanic peoples, especially the Polynesians, has been the subject of many theories. Scholars reject ideas involving a lost continent (e.g., Lemuria, Mu) or direct relations with the Middle East (e.g., the Ten Lost Tribes, migrations of Children of the Sun from Egypt), early India......
  • oceanic plate (geology)
    In areas of collision between oceanicand continentallithospheric plates such as the circum-Pacific region, the denser oceanic plate is subducted (carried into the Earth’s mantle) beneath the more buoyant continental lithosphere. Rapid subductionof the cool oceanic lithosphere perturbs the thermal regime in such a way that high pressures can be obtained at relatively low......
  • oceanic plateau (geology)
    large submarine elevation rising sharply at least 200 m (660 feet) above the surrounding deep-sea floor and characterized principally by an extensive, relatively flat or gently tilted summit. Most oceanic plateaus were named early in the 20th century prior to the invention of sonic sounding, and many of these features have been shown by modern bathymetric data to be portions of the oceanic ridges....
  • oceanic province (oceanography)
    ...and a bottom, or benthic, environment (Figure 1). Within the pelagic environment the waters are divided into the neritic province, which includes the water above the continental shelf, and the oceanic province, which includes all the open waters beyond the continental shelf. The high nutrient levels of the neritic province—resulting from dissolved materials in riverine......
  • Oceanic region (faunal region)
    This region (Figure 2) is poorly defined. It contains some localized endemics, notably the bird family Rhynochetidae (kagu) in New Caledonia. Much of the fauna, especially birds, is of demonstrable Australian affinity. ...
  • Oceanic religion
    Shamanism is prevalent in the Malay Peninsula and in Oceania. Among the peoples of the Malay Peninsula, the shaman heals with the help of celestial spirits or by using crystals of quartz. But the influence of Indo-Malayan beliefs is noticeable, too, as when shamans are said to change into tigers or to achieve trance by dancing. In the Andaman Islands the shaman gets his power from contact with......
  • oceanic ridge (geology)
    continuous submarine mountain chain extending approximately 80,000 km (50,000 miles) through all the world’s oceans. Ridges separate the oceans into distinct basins and may or may not be seismically active....
  • oceanic shoreline
    Coral reefs are masses of carbonate of lime built up from the seafloor by the accumulation of the skeletons of a profusion of animals and algae; eventually they rise to the surface of the water....
  • oceanic trench (geology)
    any long, narrow, steep-sided depression in the ocean bottom in which maximum oceanic depths (approximately 7,300 to more than 11,000 m [24,000 to 36,000 feet]) occur. The deepest known depression of this kind is the Mariana Trench, which lies east of the Mariana Islands in the western North Pacific Ocean....
  • oceanic trough (geology)
    an elongate depression in the seafloor that is characteristically shallower, shorter, narrower, and topographically gentler than oceanic trenches. Maximal depths of oceanic troughs range between 2,300 m (7,500 feet) in the Papuan Trough and 7,440 m in the Banda Trough. More typical maximum depths lie between 4 and 5 km (2.5 and 3 miles) below sea level. Lengths of the 25 best-known troughs range ...
  • Oceanid (Greek mythology)
    ...They were not immortal but were extremely long-lived and were on the whole kindly disposed toward men. They were distinguished according to the sphere of nature with which they were connected. The Oceanids, for example, were sea nymphs; the Nereids inhabited both saltwater and freshwater; the Naiads presided over springs, rivers, and lakes. The Oreads (oros, “mountain”) wer...
  • Oceanites oceanicus (bird)
    ...oceans are shorter winged, square tailed, long legged, and short toed. With wings spread, they patter over the water, “walking,” and pick up minute marine organisms. An example is Wilson’s petrel (Oceanites oceanicus), which breeds on islets along the Antarctic continent and near the Antarctic Circle and winters in the North Atlantic from about June to....
  • Oceanitidae (bird)
    any member of about 20 species of seabirds constituting the family Hydrobatidae, or sometimes considered as Oceanitidae (order Procellariiformes). Ranging in length from about 13 to 25 centimetres (5 12 to 10 inches), all are dark gray or brown, sometimes lighter below, and often with a white rump. The wings are shorter than those of most other procellariiforms ...
  • Oceanodroma leucorhoa (bird)
    ...the northern species have longer wings, forked or wedge-shaped tails, shorter legs, and longer toes; when foraging, they swoop over the water like tiny terns, occasionally alighting on the surface. Leach’s petrel (Oceanodroma leucorhoa), for example, breeds on islands in the North Atlantic and south to about 28° N in the Pacific. Several other Oceanodroma species occ...
  • oceanodromous fish
    Oceanodromous fish, which occur widely throughout the world’s oceans, live and migrate wholly in the sea. They differ mainly from one another by the method and extent of their migration....
  • Oceanographic Office (United States Navy)
    ...for domestic mapping tasks. Only when World War II brought requirements for the mapping of many foreign areas did the U.S. military become involved on a large scale, with the expansion of the Oceanographic Office (Navy), Aeronautical Chart Service (Air Force), and the U.S. Army Topographic command....
  • oceanography (science)
    scientific discipline concerned with all aspects of the world’s oceans and seas, including their physical and chemical properties, their origin and geologic framework, and the life forms that inhabit the marine environment....
  • Oceanography for Meteorologists (work by Sverdrup)
    Sverdrup wrote Oceanography for Meteorologists (1942) and was coauthor of The Oceans (1942) and of Breakers and Surf (1944)....
  • Ocean’s Eleven (motion picture [2001])
    Clooney’s next film, Ocean’s Eleven (2001), followed a group of con artists as they robbed a casino. His portrayal of Danny Ocean, the group’s ringleader, continued throughout the movie’s sequels, Ocean’s Twelve (2004) and Ocean’s Thirteen (2007). Clooney made his film directorial d...
  • Ocean’s Thirteen (motion picture)
    ...He portrayed one of several con men who join forces in the Ocean’s trilogy—Ocean’s Eleven (2001), Ocean’s Twelve (2004), and Ocean’s Thirteen (2007). The films feature an all-star cast that includes George Clooney and Brad Pitt. In the Jason Bourne series—The Bo...
  • Ocean’s Twelve (motion picture)
    ...in two film series that were hugely popular. He portrayed one of several con men who join forces in the Ocean’s trilogy—Ocean’s Eleven (2001), Ocean’s Twelve (2004), and Ocean’s Thirteen (2007). The films feature an all-star cast that includes George Clooney and Brad Pitt. In the Jason ...
  • Oceanside (California, United States)
    city, San Diego county, southern California, U.S. Situated about 35 miles (55 km) north of San Diego, Oceanside lies along the Pacific coast, at the mouth of the San Luis Rey River. The region was originally territory of the Luiseño Indians. Bounded to the south by Carlsbad and to the east by Vista, it developed as ...
  • Oceanus (Greek mythology)
    in Greek mythology, the river that flowed around the Earth (conceived as flat), for example, in the shield of Achilles described in Homer’s Iliad, Book XVIII. Beyond it, to the west, were the sunless land of the Cimmerii, the country of dreams, and the entrance to the underworld. In Hesiod’s Theogony, Oceanus was the oldest Titan, the son of Uranus...
  • Oceanus Britannicus (channel, Europe)
    narrow arm of the Atlantic Ocean separating the southern coast of England from the northern coast of France and tapering eastward to its junction with the North Sea at the Strait of Dover (French: Pas de Calais). With an area of some 29,000 square miles (75,000 square kilometres), it is the smallest of the shallow seas covering the continental shelf of Europe. From its mouth in the North Atlantic ...
  • ocellated antbird (bird)
    ...may occur whether or not there is social behaviour in the usual sense. Among several species of birds that follow swarms of army ants in Panama to catch insects flushed by the ants, the big ocellated antbird (Phaenostictus mcleannani) is dominant, the medium-sized bicoloured antbird (Gymnopithys bicolor) is next, and the small, spotted antbird (Hylophylax......
  • ocellated turkey (bird)
    ...turkey (Meleagris gallopavo), a native game bird of North America but widely domesticated for the table. The other species is Agriocharis (or Meleagris) ocellata, the ocellated turkey. For unrelated but similar birds, see bustard (Australian turkey); megapode (brush turkey); snakebird (water turkey)....
  • ocelli (anatomy)
    ...the transmission of nerve impulses. Statocysts, located between the tentacles or near the tentacular base, inform the animal of its orientation with respect to gravitational forces. Light-sensitive ocelli (external patches of pigment and photoreceptor cells organized in either a flat disk or a pit) occur in some medusae of each of the three classes that possess this stage. Such sensory......
  • ocellus (anatomy)
    ...the transmission of nerve impulses. Statocysts, located between the tentacles or near the tentacular base, inform the animal of its orientation with respect to gravitational forces. Light-sensitive ocelli (external patches of pigment and photoreceptor cells organized in either a flat disk or a pit) occur in some medusae of each of the three classes that possess this stage. Such sensory......
  • ocelot (mammal)
    spotted cat of the New World, found in lowland areas from Texas southward to northern Argentina. The short, smooth fur is patterned with elongated, black-edged spots that are arranged in chainlike bands. The cat’s upper parts vary in colour from light or tawny yellow to gray. There are small black spots on the head, two black stripes on each cheek, and four or five black stripes along the n...
  • OCHA (international organization)
    agency of the United Nations (UN) Secretariat originally established in 1972 to coordinate international relief activities to countries struck by natural or other disasters. It is headed by a disaster relief coordinator who reports directly to the UN secretary-general and works closely with the United Nations Development Programme (UNDP)....
  • ocher (earth pigment)
    Paint and painting were thought to animate sculpture—often literally, in religiosymbolic terms, as paint was considered to have magical, vivifying powers. Paints were generally ochres, with some vegetable-derived pigments. Water was the usual medium, occasionally supplemented with sap. Brushes were the fibrous ends of chewed or frayed sticks, small feather bundles, pieces of wood, and......
  • Ocherki russkoy smuty (work by Denikin)
    ...the remainder of his army was then evacuated to the Crimea (March 1920). In April Denikin turned over his command to General Pyotr N. Wrangel and settled in France, where he wrote his memoirs, Ocherki russkoy smuty, 5 vol. (1923–27; “History of the Civil Strife in Russia”). He immigrated to the United States in 1945....
  • ochetus (music)
    in medieval polyphonic (multipart) music, the device of alternating between parts, single notes, or groups of notes. The result is a more or less continuous flow with one voice resting while the other voice sounds....
  • Ochiba (painting by Hishida)
    ...Japanese line drawing with a Western Impressionistic style (pejoratively known as mōrōtai, or “vague,” “indistinct”). Among his best-known works are “Ochiba” (1909; “Fallen Leaves”) and “Kuroi neko” (1910; “A Black Cat”)....
  • Ochikubo monogatari (Japanese novel)
    Further images of Japanese musical life can be captured from the Heian period (794–1185). In the very first chapter of the 10th-century Ochikubo monogatari, one of Japan’s earliest novels, the sad fate of the heroine is noted by the fact that she was never able to learn how to play the Chinese seven-stringed ch’in zither, although she did have some training in Ja...
  • Ochino, Bernardino (Italian religious reformer)
    Protestant convert from Roman Catholicism who became an itinerant Reformer and influenced other radical Reformers by his controversial anti-Catholic views....
  • Ochna (plant genus)
    Protestant convert from Roman Catholicism who became an itinerant Reformer and influenced other radical Reformers by his controversial anti-Catholic views.......
  • Ochna multiflora (plant)
    ...has nearly 90 species. Members of the family usually have alternate, simple leaves with closely parallel lateral veins and obvious stipules. Their flowers usually have five petals and sepals. Fun shrub, or carnival bush (Ochna multiflora), reaches 1.5 metres (5 feet) and has evergreen leaves. Its yellow, buttercup-like flowers have sepals that turn scarlet and remain after the......
  • Ochnaceae (plant family)
    a family of the order Malpighiales, comprising 27 genera and some 495 species of tropical trees and shrubs, with a few genera of herbs. Many species are native to Brazil. The largest genus is Ouratea (including Gomphia), with about 200 species. The tropical African and Asian genus Ochna has nearly 90 species. Members of the family usually have alternate, simple leaves with clo...
  • Ocho comedias, y ocho entremeses nuevos (work by Cervantes)
    ...(1580s; “The Traffic of Algiers”). He names nine plays, the titles of a few of which sound like the originals of plays reworked and published years later in the collection Ocho comedias, y ocho entremeses nuevos (1615; “Eight Plays and Eight New Interludes”). Fixed theatre sites were just becoming established in the major cities of Spain, and there......
  • Ocho Rios (Jamaica)
    town and Caribbean port on the north coast of Jamaica, northwest of Kingston. The Spanish name means “eight rivers,” in reference to the number of rivers in the area. The 600-foot (180-metre) cataracts of Dunns River Falls make Ocho Rios a popular tourist resort, and the town has numerous hotels as well as cruise ship facilities. As a trade centre, it serves an are...
  • Ochoa, Ellen (American engineer and astronaut)
    American engineer and the first Hispanic female astronaut....
  • Ochoa, Lorena (Mexican golfer)
    Golfer Lorena Ochoa, already recognized as one of Mexico’s all-time sports stars, carried the hopes of a nation on her shoulders with ease, and in 2007 she took over from Sweden’s Annika Sörenstam as the world number one-ranked woman player, achieved her first major title, and (with 8 victories in 25 tournaments) established record earnings for one season on the Ladies Profess...
  • Ochoa, Severo (Spanish-American biochemist)
    biochemist and molecular biologist who received (with the American biochemist Arthur Kornberg) the 1959 Nobel Prize for Physiology or Medicine for discovery of an enzyme in bacteria that enabled him to synthesize ribonucleic acid (RNA), a substance of central importance to the synthesis of proteins by the cell....
  • Ochoan Stage (geology)
    ...of Petroleum Geologists in 1939 established North American standard reference sections for the Permian consisting of four series—namely, the Wolfcampian, Leonardian, Guadalupian, and Ochoan—on the basis of the succession in West Texas and New Mexico....
  • Ochotona (mammal)
    small short-legged and virtually tailless egg-shaped mammal found in the mountains of western North America and much of Asia. Despite their small size, body shape, and round ears, pikas are not rodents but the smallest representatives of the lagomorphs, a group otherwise represented only by hares and rabbits (family Leporidae)....
  • Ochotona collaris (mammal)
    ...roughly half of the Asian species live in rocky habitats and do not make burrows. Rather, their nests are made deep in a labyrinth of talus adjoining alpine meadows or other suitable vegetation. The collared pika (O. collaris) of Alaska and northern Canada has been found on the isolated nunataks (crags or peaks surrounded by glaciers) in Kluane National Park, and......
  • Ochotona hyperborea (mammal)
    ...in Kluane National Park, and O. macrotis has been recorded at 6,130 metres (20,113 feet) on the slopes of the Himalayas. The pika with the largest distribution, the northern pika (O. hyperborea), ranges from the Ural Mountains to the east coast of Russia and Hokkaido Island of northern Japan. Although the northern pika is considered......
  • Ochotona koslowi (mammal)
    ...as the pika is a keystone species for biodiversity in this region. Four Asian pikas—three in China and one in Russia and Kazakhstan—are listed as endangered species. One of these, Koslov’s pika (O. koslowi) from China, was originally collected by the Russian explorer Nikolai Przewalski in 1884, and approximately 100 years passed before it was se...
  • Ochotona macrotis (mammal)
    ...O. collaris) of Alaska and northern Canada has been found on the isolated nunataks (crags or peaks surrounded by glaciers) in Kluane National Park, and O. macrotis has been recorded at 6,130 metres (20,113 feet) on the slopes of the Himalayas. The pika with the largest distribution, the northern pika (O.......
  • Ochotona princeps (mammal)
    ...O. collaris) of Alaska and northern Canada has been found on the isolated nunataks (crags or peaks surrounded by glaciers) in Kluane National Park, and O. macrotis has been recorded at 6,130 metres (20,113 feet) on the slopes of the Himalayas. The pika with the largest distribution, the northern pika (O..........
  • Ochotona pusilla (mammal)
    ...is successful only when the first offspring are lost early in the breeding season. Litter size of most rock dwellers is low, but burrowing pikas may produce multiple large litters each season. The steppe pika (O. pusilla) has been reported to have litters of as many as 13 young and breed up to five times in a year....
  • Ochotonidae (mammal family)
    ...term pika comes from the vernacular piika of the Tunguses, a tribe from northeastern Siberia. Ochotona is the sole living genus of the family Ochotonidae, and its members lack several special skeletal modifications present in hares and rabbits (family Leporidae), such as a highly arched skull, relatively upright posture of the head, strong....
  • Ochotskoje More (sea, Pacific Ocean)
    northwestern arm of the Pacific Ocean, bounded on the west and north by the east coast of Asia from Cape Lazarev to the mouth of the Penzhina River, on the east and southeast by the Kamchatka Peninsula and the Kuril Islands, on the south by the northern coast of the Japanese island of Hokkaido, and on the southwest by Sakhalin Island. Except for the small area touching Hokkaido,...
  • ochre (earth pigment)
    Paint and painting were thought to animate sculpture—often literally, in religiosymbolic terms, as paint was considered to have magical, vivifying powers. Paints were generally ochres, with some vegetable-derived pigments. Water was the usual medium, occasionally supplemented with sap. Brushes were the fibrous ends of chewed or frayed sticks, small feather bundles, pieces of wood, and......
  • Ochrida (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....
  • Ochroma lagopus (tree)
    common, fast-growing tropical tree, occurring from southern Mexico to Bolivia, that is noted for its extremely lightweight and light-coloured wood. Balsa has pale bark and, like many tropical trees, has no annual growth rings. It can grow more than 5 metres (16.5 feet) per year in full sun, reaching a maximum height of about 30 metres (100 feet). The large leaves, generally concentrated at the end...
  • Ochroma pyramidale (tree)
    common, fast-growing tropical tree, occurring from southern Mexico to Bolivia, that is noted for its extremely lightweight and light-coloured wood. Balsa has pale bark and, like many tropical trees, has no annual growth rings. It can grow more than 5 metres (16.5 feet) per year in full sun, reaching a maximum height of about 30 metres (100 feet). The large leaves, generally concentrated at the end...
  • Ochromonas (algae genus)
    ...silica cysts (statospores); predominantly freshwater; approximately 1,200 species; Chrysamoeba, Chrysocapsa, and Ochromonas.Class DictyochophyceaePredominantly marine flagellates, including silicoflagellates that form skeletons commo...
  • ochronosis (pathology)
    ...and oxidation, it imparts a black colour. The remainder is deposited in cartilage and, to a lesser degree, in the skin and sclerae. The resultant darkening of these tissues by this pigment is termed ochronosis and is accompanied by gradual erosion of cartilage and progressive joint disease....
  • ochronotic arthropathy (pathology)
    Ochronotic arthropathy results from another, rarer inborn error of metabolism. It is characterized by pigmentation and degeneration of hyaline cartilage and by defective breakdown of the amino acids tyrosine and phenylalanine, causing large amounts of homogentisic acid to accumulate in body fluids and the urine. The urine turns black when exposed to air, a phenomenon called alkaptonuria. After......
  • Ochs, Adolph Simon (American newspaper publisher)
    American newspaper publisher under whose ownership (from 1896) The New York Times became one of the world’s outstanding newspapers. Despising “yellow [sensational] journalism,” he emphasized comprehensive and trustworthy news gathering....
  • Ochs, Peter (Swiss revolutionary)
    Swiss revolutionary who wrote most of the constitution of the unitary Helvetic Republic (1798)....
  • Ochs, Phil (American folksinger and songwriter)
    American folksinger and songwriter best remembered for the protest songs he wrote in the 1960s on topics ranging from the Vietnam War to civil rights....
  • Ochsenbein, Johann Ulrich (Swiss politician)
    Swiss politician and military leader who headed the confederation government during the Sonderbund War (1847) and presided over the constitutional reform committee of 1848....
  • Ochsenbein, Ulrich (Swiss politician)
    Swiss politician and military leader who headed the confederation government during the Sonderbund War (1847) and presided over the constitutional reform committee of 1848....
  • Ochsenfeld, R. (German physicist)
    ...temperature, called the transition temperature, usually close to absolute zero. The Meissner effect, a property of all superconductors, was discovered by the German physicists W. Meissner and R. Ochsenfeld in 1933....
  • “ochsenfurter Männerquartett, Das” (work by Frank)
    ...of capitalism and the establishment of socialism was expressed in his novel Der Bürger (1924; A Middle-Class Man) and in Das ochsenfurter Männerquartett (1927; The Singers). During the same period he wrote his masterpiece, Karl und Anna (1926; Carl and Anna), a realistic, if sentimental, account of a soldier who seduces his comrade’...
  • Ochteridae (insect)
    any insect of the family Ochteridae (order Heteroptera), which numbers about 25 species. These insects resemble tiny toads, are about 4 or 5 mm (almost 0.2 inch) long, and live among plants near streams and ponds. As indicated by their common name, the body surface is smooth and velvetlike. The front legs are slender and are developed for running....
  • Ochus (king of Persia)
    Achaemenid king of Persia (reigned 359/358–338 bc)....
  • Ocimum (plant genus)
    Of the 150 tropical species of Ocimum, one sacred to Hindus is basil, or tulsī (Ocimum basilicum); this plant is native in Africa and Asia but is cultivated as a culinary herb in other regions (see basil). The genus Origanum, native in Europe, includes 15 to 20 species, chief among them being......
  • Ocimum basilicum (spice)
    spice consisting of the dried leaves of Ocimum basilicum, an annual herb of the family Lamiaceae (Labiatae) native to India and Iran. A number of varieties are used in commerce including the small-leaf common basil, the larger leaf Italian basil, and the large lettuce-leaf basil. The dried large-leaf varieties have a fragrant aroma faintly reminiscent of anise, and a warm...
  • Ockeghem, Jean de (Flemish composer)
    composer of sacred and secular music, one of the great masters of the Franco-Flemish style that dominated European music of the Renaissance....
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