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  • Português

    Portuguese language, Romance language that is spoken in Portugal, Brazil, and other Portuguese colonial and formerly colonial territories. Galician, spoken in northwestern Spain, is closely related to Portuguese. Portuguese owes its importance—as the second Romance language (after Spanish) in terms

  • Portuguesa (state, Venezuela)

    Portuguesa, estado (state), northwestern Venezuela. It is bordered by the states of Lara (north), Cojedes (east), Barinas (south), and Trujillo (west). The northwestern portion of the territory is in the Cordillera de Mérida, the rest being in the Llanos (plains). The main economic activity in

  • Portuguese Airlines (Portuguese company)

    Mozambique: Transportation and telecommunications: …but after World War II Portugal’s national airline opened a route between Beira and Maputo. Eventually colonial Mozambique developed its own airline. It was replaced in 1980 by Mozambique Airlines (Linhas Aéreas de Moçambique; LAM), the national carrier, which also provides international service. Mozambique has a number of domestic airports…

  • Portuguese bullfighting (sport)

    bullfighting: Development in the modern era: The opposite development occurred in Portugal. While mounted bullfighting waned in Spain and was transformed by the masses into the foot-based corrida common today, equestrian bullfighting was finely honed into an art and a national specialty in Portugal. The main performers in a Portuguese bullfight are the rejoneadores (lancers mounted…

  • Portuguese court (Spanish and Portuguese parliament)

    Cortes, a representative assembly, or parliament, of the medieval Iberian kingdoms and, in modern times, the national legislature of Spain and of Portugal. The Cortes developed in the Middle Ages when elected representatives of the free municipalities acquired the right to take part in the

  • Portuguese East Africa

    Mozambique, a scenic country in southeastern Africa. Mozambique is rich in natural resources, is biologically and culturally diverse, and has a tropical climate. Its extensive coastline, fronting the Mozambique Channel, which separates mainland Africa from the island of Madagascar, offers some of

  • Portuguese Guinea

    Guinea-Bissau, country of western Africa. Situated on the Atlantic coast, the predominantly low-lying country is slightly hilly farther inland. The name Guinea remains a source of debate; it is perhaps a corruption of an Amazigh (Berber) word meaning “land of the blacks.” The country also uses the

  • Portuguese India (historic region, India)

    Portuguese India, name once used for those parts of India which were under Portuguese rule from 1505 to December 1961. Portuguese India consisted of several isolated tracts: (1) the territory of Goa with the capital, a considerable area in the middle of the west coast of India; (2) Damão, or Daman,

  • Portuguese language

    Portuguese language, Romance language that is spoken in Portugal, Brazil, and other Portuguese colonial and formerly colonial territories. Galician, spoken in northwestern Spain, is closely related to Portuguese. Portuguese owes its importance—as the second Romance language (after Spanish) in terms

  • Portuguese literature

    Portuguese literature, the body of writing in the Portuguese language produced by the peoples of Portugal, which includes the Madeira Islands and the Azores. The literature of Portugal is distinguished by a wealth and variety of lyric poetry, which has characterized it from the beginning of its

  • Portuguese man-of-war (invertebrate)

    Portuguese man-of-war, (genus Physalia), any of various jellylike marine animals of the order Siphonophora (class Hydrozoa, phylum Cnidaria) noted for their colonial bodies, floating habit, and powerful sting. The man-of-war is one of the best-known siphonophores. The man-of-war, although found in

  • Portuguese oak (plant)

    oak: trojana), and Portuguese oak (Q. lusitanica). Popular Asian ornamentals include the blue Japanese oak (Q. glauca), daimyo oak (Q. dentata), Japanese evergreen oak (Q. acuta), and sawtooth oak (Q. acutissima). The English oak, a timber tree native to Eurasia and northern Africa, is

  • Portuguese Republic

    Portugal, country lying along the Atlantic coast of the Iberian Peninsula in southwestern Europe. Once continental Europe’s greatest power, Portugal shares commonalities—geographic and cultural—with the countries of both northern Europe and the Mediterranean. Its cold, rocky northern coast and

  • Portuguese Socialist Action (political party, Portugal)

    Mário Soares: …which later transformed into the Portuguese Socialist Party (Partido Socialista Portuguesa). By the time the army-imposed right-wing dictatorship fell in 1974, Soares had been jailed 12 times and had twice experienced exile, in São Tomé (1968) and Paris (1970–74).

  • Portuguese Socialist Party (political party, Portugal)

    Mário Soares: …which later transformed into the Portuguese Socialist Party (Partido Socialista Portuguesa). By the time the army-imposed right-wing dictatorship fell in 1974, Soares had been jailed 12 times and had twice experienced exile, in São Tomé (1968) and Paris (1970–74).

  • Portuguese sundew (plant)

    carnivorous plant: Major families: Once classified within Droseraceae, the Portuguese sundew (Drosophyllum lusitanicum) is now placed within its own family, Drosophyllaceae (order Caryophyllales), of which it is the only species.

  • Portuguese West Africa

    Angola, country located in southwestern Africa. A large country, Angola takes in a broad variety of landscapes, including the semidesert Atlantic littoral bordering Namibia’s “Skeleton Coast,” the sparsely populated rainforest interior, the rugged highlands of the south, the Cabinda exclave in the

  • Portuguese, The (painting by Braque)

    Georges Braque: Cubism: …1911, he stenciled letters into The Portuguese.

  • Portulaca (plant)

    Purslane, any of certain small, fleshy annual plants of the genus Portulaca (40–100 species), of the family Portulacaceae. The plants have prostrate, often reddish stems, with spoon-shaped leaves and flowers that open in the sunlight. The common purslane (P. oleracea), or pusley, is a widespread

  • Portulaca grandiflora (plant, Portulaca grandiflora)

    purslane: Rose moss (P. grandiflora), a trailing fleshy species, is cultivated as a garden ornamental for its brightly coloured, sometimes doubled flowers. All plants of the genus are known for their persistence; they grow well even in dry waste soil and can retain enough moisture to…

  • Portulaca oleracea (plant)

    purslane: The common purslane (P. oleracea), or pusley, is a widespread weed, recognizable by its small yellow flowers. P. oleracea sativa, known as kitchen garden pusley, is grown to some extent as a potherb, mostly in Europe. Rose moss (P. grandiflora), a trailing fleshy species, is cultivated…

  • Portulaca oleracea sativa (plant)

    purslane: oleracea sativa, known as kitchen garden pusley, is grown to some extent as a potherb, mostly in Europe. Rose moss (P. grandiflora), a trailing fleshy species, is cultivated as a garden ornamental for its brightly coloured, sometimes doubled flowers. All plants of the genus are known for their persistence;…

  • Portulacaceae (plant family)

    Portulacaceae, the purslane family of flowering plants, in the order Caryophyllales, with about 15 genera and 500 species of herbs or small shrubs, native primarily to the Pacific coast of North America and southern South America. Members of the family have leaves that often are fleshy and

  • Portulacaria afra (plant)

    purslane: The purslane tree (Portulacaria afra), native to South Africa, is a fleshy-leaved, soft-wooded tree up to 4 metres (13 feet) high. It is grown in California as a specimen plant for its succulent habit and its tiny pink flowers that grow in clusters; it is also…

  • Portunidae (crustacean)

    Swimming crab, any member of the family Portunidae (order Decapoda of the class Crustacea, phylum Arthropoda). In these animals, the fifth (hindmost) pair of legs are flattened into paddles for swimming. The family includes the blue crab (Callinectes sapidus), an edible crab of the Atlantic coast

  • Portunol (dialect)

    Uruguay: Ethnic groups and languages: …often in a slang called portuñol, from the words português and español.

  • Portuondo, Omara (Cuban singer)

    Cuba: Music and dance: …Ibrahim Ferrer, Rubén González, and Omara Portuondo. Classical music is of relatively minor importance in Cuba, but there is a National Symphony Orchestra that also has a chamber orchestra and instrumental ensembles.

  • Portus (ancient Rome)

    Portus, harbour town of imperial Rome. The artificial harbour at Portus, constructed by the emperor Claudius I (ad 41–54) to replace Ostia (q.v.), was connected to Rome by canal and the Tiber River. After about 200 ships were lost in the harbour during a storm in ad 62, Trajan added a second

  • portus (medieval settlement)

    history of the Low Countries: Economy: Smaller trade settlements (portus, or vicus) emerged at Tournai, Ghent, Brugge, Antwerp, Dinant, Namur, Huy, Liège, and Maastricht—a clear indication of the commercial importance of the Schelde and the Meuse.

  • Portus Albus (ancient Rome)

    Algeciras: …the site of the Roman Portus Albus; its Arabic name, Al-Jazīrah al-Khaḍrāʾ, means Green Island, in reference to the offshore Isla Verde. The port was taken by Alfonso XI of Castile in 1344 and then was recaptured and destroyed in 1368 by the Moors. It was refounded in 1704 by…

  • Portus Cale (Portugal)

    Porto, city and port, northern Portugal. The city lies along the Douro River, 2 miles (3 km) from the river’s mouth on the Atlantic Ocean and 175 miles (280 km) north of Lisbon. World-famous for its port wine, Porto is Portugal’s second largest city and is the commercial and industrial centre for

  • Portus Gaditanus (Spain)

    Puerto Real, town, Cádiz provincia (province), in the Andalusia comunidad autónoma (autonomous community), southern Spain. It is on the north shore of the inner arm of the Bay of Cádiz and lies 5 miles (8 km) east of Cádiz. Known to the Romans, it was probably the most ancient trading station on

  • Portus Magnus (ancient Rome)

    Arzew: …near the ruined Roman settlement, Portus Magnus. Petrochemical products, esparto grass, salt (from Salines d’Arzew, 9 miles [11 km] south), wine, cereals, and cattle are exported, and there is some commercial fishing. Arzew is connected by pipelines with the Hassi RʾMel natural gas fields and the Hassi Messaoud oil fields.…

  • Portus Magnus (Spain)

    Almería, port city and capital of Almería provincia (province), in the comunidad autónoma (autonomous community) of Andalusia, southern Spain, on the Mediterranean Gulf of Almería. Known to the Romans as Portus Magnus and to the Moors as Al-Marīyah (“Mirror of the Sea”), it was captured by the

  • Portus Magonis (Spain)

    Maó, capital of Minorca Island, Balearic Islands provincia (province) and comunidad autónoma (autonomous community), Spain. It originated as the Mediterranean Portus Magonis, bearing the name of the Carthaginian general Mago. Under the Romans it was a municipium (privileged town). The Arab pirate

  • Portus Menesthei (Spain)

    El Puerto de Santa María, port city, Cádiz provincia (province), in the Andalusia comunidad autónoma (autonomous community), southern Spain, at the mouth of Guadalete River on the Bay of Cádiz, southwest of Jerez de la Frontera. The Roman Portus Menesthei, it was once the site of naval arsenals and

  • Portus Naonis (Italy)

    Pordenone, city, Friuli–Venezia Giulia regione, northeastern Italy. It lies along a small tributary of the Meduna River, southwest of Udine. Originating as the Roman and medieval river port of Portus Naonis, it was a bulwark of the Trevisani in their war against Aquileia until it was destroyed by

  • Portus Victoriae (ancient Rome)

    Santander: …of the Roman colony of Portus Victoriae. The centre of the lower town was rebuilt after it was destroyed by fire spread by a windstorm in 1941. Notable surviving buildings include the Magdalena Palace, presented by the town to King Alfonso XIII; a Gothic cathedral; the library of the contemporary…

  • Portzamparc, Christian de (French architect and urban planner)

    Christian de Portzamparc, French architect and urban planner whose distinctly modern and elegant designs reflected his sensitivity to and understanding of the greater urban environment. He was the first French architect to win the Pritzker Prize (1994). Portzamparc’s interest in architecture and

  • Porus (Indian prince)

    Porus, Indian prince who ruled the region between the Hydaspes (Jhelum) and Acesines (Chenab) rivers at the time of Alexander the Great’s invasion (327–326 bce) of the Punjab. Unlike his neighbour, Ambhi, the king of Taxila (Takshashila), Porus resisted Alexander. But with his elephants and

  • porus opticus (anatomy)

    human eye: The orbit: The optic foramen, the opening through which the optic nerve runs back into the brain and the large ophthalmic artery enters the orbit, is at the nasal side of the apex; the superior orbital fissure is a larger hole through which pass large veins and nerves.…

  • Porvoo (Finland)

    Porvoo, city, southern Finland, at the mouth of the Porvoo River on the Gulf of Finland, northeast of Helsinki. About one-third of the population is Swedish speaking. One of Finland’s oldest communities, it has been a trade centre since the early 14th century and received town rights in 1346. It

  • Porvoo Diet (Finnish politics)

    Finland: The era of bureaucracy: …was laid down by the Porvoo (Borgå) Diet in 1809. Finland was still formally a part of Sweden until the peace treaty of Hamina (Fredrikshamn) later that year, but most of the Finnish leaders had already grown tired of Swedish control and wanted to acquire as much self-government as possible…

  • Porzana (bird genus)

    crake: The most widespread genus is Porzana (13 species), typified by the spotted crake (P. porzana) found in Europe and eastward to Mongolia; in winter it reaches southern Asia and northern Africa. It is a brown bird 25 cm (10 inches) long with a light-spotted breast and buffy undertail. Its New…

  • Porzana carolina (bird)

    crake: …New World counterpart is the sora, or Carolina rail (P. carolina). The sora is about 23 cm (9 inches) long and grayish brown with black on the face and throat, with a short yellow bill. Other Porzana species are Baillon’s crake (P. pusilla), occurring in parts of Europe, Asia, Africa,…

  • Porzana parva (bird)

    crake: …to the Philippines; and the little crake (P. parva), a relatively common Eurasian form.

  • Porzana porzana (bird)

    crake: … (13 species), typified by the spotted crake (P. porzana) found in Europe and eastward to Mongolia; in winter it reaches southern Asia and northern Africa. It is a brown bird 25 cm (10 inches) long with a light-spotted breast and buffy undertail. Its New World counterpart is the sora, or…

  • Porzellan Manufaktur Nymphenburg (factory, Munich, Germany)

    pottery: Pottery factories: …Nymphenburg, at Munich, now the Porzellan Manufaktur Nymphenburg. At the beginning of the 20th century, it began to use a wider range of underglaze colours with the aid of colour chemists from Sèvres and, about the same time, reissued some of the old figures and services of Bustelli and Auliczek…

  • Posada, José Guadalupe (Mexican printmaker)

    José Guadalupe Posada, printmaker whose works, often expressionistic in content and style, were influential in the development of 20th-century graphic art. As a child, Posada worked as a farm labourer and in a pottery factory. He taught school for a short time and then began to draw, inspired

  • Posadas (Argentina)

    Posadas, city, capital of Misiones provincia (province), northeastern Argentina. Situated in the western corner of the province, it is bordered (north and east) by the Paraná River, which separates it from Encarnación, Paraguay. The settlement originated as a Paraguayan trading post and river port,

  • Posadas (Christmas morality play)

    Native American dance: Mexico and Mesoamerica: Posadas and pastorelas are danced episodes of the Christmastime coloquio de los pastores (“shepherds’ play”). Most popular in southern and central Mexico and the U.S. states of New Mexico and Texas, the posadas are generally processions by city boys and girls who go from house…

  • Posadas, Las (Mexican festival)

    Las Posadas, (Spanish: “The Inns”) religious festival celebrated in Mexico and some parts of the United States between December 16 and 24. Las Posadas commemorates the journey that Joseph and Mary made from Nazareth to Bethlehem in search of a safe refuge where Mary could give birth to the baby

  • poṣadha (Jainism)

    Paryuṣaṇa: …of monks, an observance called poṣadha. The fourth day of Paryuṣaṇa coincides with the birth anniversary of Mahāvīra.

  • posadha (Buddhism)

    Uposatha, fortnightly meetings of the Buddhist monastic assembly, at the times of the full moon and the new moon, to reaffirm the rules of discipline. The uposatha observance, now confined almost entirely to the Theravāda (“Way of the Elders”) tradition of Southeast Asia, can be traced back to

  • posaune (musical instrument)

    Trombone, brass wind musical instrument sounded by lip vibration against a cup mouthpiece. It has an extendable slide that can increase the length of the instrument’s tubing. The slide thus performs the function of the valves on other brass instruments. From the 19th century, some trombones have

  • Poseidon (Greek mythology)

    Poseidon, in Greek religion, god of the sea (and of water generally), earthquakes, and horses. He is distinguished from Pontus, the personification of the sea and the oldest Greek divinity of the waters. The name Poseidon means either “husband of the earth” or “lord of the earth.” Traditionally, he

  • Poseidon Adventure, The (film by Neame [1972])

    Jack Albertson: …in the popular disaster movie The Poseidon Adventure (1972). He also had guest roles in dozens of TV series and variety shows as well as several made-for-television movies. He showed his versatility as an actor by garnering awards in three media; he won a Tony Award in 1965 for his…

  • Poseidon missile (military technology)

    Poseidon missile, U.S. submarine-launched ballistic missile introduced in 1971 to replace the Polaris missile. The two-stage Poseidon had about the same range as its predecessor (2,800 miles [4,500 km]), but it could carry up to 14 independently targetable nuclear warheads and deliver them with

  • Poseidonia (ancient city, Italy)

    Paestum, ancient city in southern Italy near the west coast, 22 miles (35 km) southeast of modern Salerno and 5 miles (8 km) south of the Sele (ancient Silarus) River. Paestum is noted for its splendidly preserved Greek temples. Poseidonia was probably founded about 600 bc by Greek colonists from

  • Poseidonius (Greek philosopher)

    Poseidonius, Greek philosopher, considered the most-learned man of his time and, possibly, of the entire Stoic school. Poseidonius, nicknamed “the Athlete,” was a native of Apamea in Syria and a pupil of the Greek Stoic philosopher Panaetius. He spent many years in travel and scientific research in

  • Posen (Poland)

    Poznań, city, capital of Wielkopolskie województwo (province), west-central Poland, located on the Warta River near its confluence with the Cybina. Beginning as a small stronghold in the 9th century, Poznań became the capital of Poland (with Gniezno) and the residence of Poland’s first two

  • Posen, Zac (American fashion designer)

    Zac Posen, American fashion designer best known for his glamorous evening gowns and cocktail dresses. Posen was raised in the SoHo neighbourhood of Lower Manhattan. His father, Stephen Posen, was a painter, and his mother, Susan, was a corporate attorney. He showed an interest in fashion at an

  • Posen, Zachary E. (American fashion designer)

    Zac Posen, American fashion designer best known for his glamorous evening gowns and cocktail dresses. Posen was raised in the SoHo neighbourhood of Lower Manhattan. His father, Stephen Posen, was a painter, and his mother, Susan, was a corporate attorney. He showed an interest in fashion at an

  • Posener, Edith Claire (American costume designer)

    Edith Head, American motion-picture costume designer. Head was the daughter of a mining engineer, and she grew up in various towns and camps in Arizona, Nevada, and Mexico. She attended the University of California (B.A.) and Stanford University (M.A.). After a time as a schoolteacher and some

  • posey (floral decoration)

    Nosegay, small, hand-held bouquet popular in mid- 19th-century Victorian England as an accessory carried by fashionable ladies. Composed of mixed flowers and herbs and edged with a paper frill or greens, the arrangement was sometimes inserted into a silver filigree holder. When supplied by an

  • Posh Spice (English singer and designer)

    Victoria Beckham, English singer and designer who gained stardom in the mid-1990s as a member of the pop band Spice Girls and later launched a successful line of clothing and accessories. At age 20, Adams was one of the five young women selected to create the music group Spice Girls. The media

  • Poshchochina obshchestvennomu vkusu (Russian manifesto)

    David Davidovich Burlyuk: …Futurism, Poshchochina obshchestvennomu vkusu (A Slap in the Face of Public Taste). In 1913–14 he took part in a “Futurist tour” of lectures and poetry readings throughout Russia with the poets Mayakovsky and Vasily Kamensky. It was because of his activity in all these fields that he was soon…

  • Posidonius (Greek philosopher)

    Poseidonius, Greek philosopher, considered the most-learned man of his time and, possibly, of the entire Stoic school. Poseidonius, nicknamed “the Athlete,” was a native of Apamea in Syria and a pupil of the Greek Stoic philosopher Panaetius. He spent many years in travel and scientific research in

  • Posies of George Gascoigne, The (work by Gascoigne)

    George Gascoigne: In The Posies of George Gascoigne (1575), an authorized revision of the earlier work, which had been published anonymously, he included also “Certayne notes of Instruction,” the first treatise on prosody in English. In The Steele Glas (1576), one of the earliest formal satires in English,…

  • position (prosody)

    Position, in Greek or Latin prosody, the condition of having a short vowel followed by two consonants or a double consonant (such as -pp- in the Greek word hippos), which makes its syllable long. Such a syllable is said to be long by position, in contrast to a syllable having a long vowel or a

  • position feedback control system (technology)

    automation: Numerical control: A position feedback control system is used in most NC machines to verify that the coded instructions have been correctly performed.

  • position finding (navigation)

    surveying: Hydrography: Modern position-fixing techniques using radar have made the whole process much simpler, for the ship’s location is now known continuously with reference to fixed stations on shore or to satellite tracks. Another modern technique is the use of pictures taken from aircraft or satellites to indicate…

  • position keeping (aviation)

    formation flying: This is called “position keeping.” Any change in relative position between aircraft is considered movement by the wingmen.

  • position vector (mechanics)

    Position vector, straight line having one end fixed to a body and the other end attached to a moving point and used to describe the position of the point relative to the body. As the point moves, the position vector will change in length or in direction or in both length and direction. If drawn to

  • positional astronomy (astronomy)

    star: Stellar positions: Accurate observations of stellar positions are essential to many problems of astronomy. Positions of the brighter stars can be measured very accurately in the equatorial system (the coordinates of which are called right ascension [α, or RA] and

  • positional numeral system (mathematics)

    Archimedes: His works: …effect, is to create a place-value system of notation, with a base of 100,000,000. (That was apparently a completely original idea, since he had no knowledge of the contemporary Babylonian place-value system with base 60.) The work is also of interest because it gives the most detailed surviving description of…

  • positioning (business)

    marketing: Positioning: A key step in marketing strategy, known as positioning, involves creating and communicating a message that clearly establishes the company or brand in relation to competitors. Thus, Volvo Aktiebolaget (Sweden) has positioned its automobile as the “safest,” and Daimler-Benz AG (Germany), manufacturer of Mercedes-Benz…

  • positive acceleration stress (physiology)

    acceleration stress: Positive acceleration stress: Positive acceleration stress occurs when the direction of acceleration is along the long axis of the body from head to foot. As acceleration increases the force exerted on the pilot from 1 g to 2 g, there is an awareness of increased…

  • positive assortative mating (genetics)

    assortative mating: Positive assortative mating, or homogamy, exists when people choose to mate with persons similar to themselves (e.g., when a tall person mates with a tall person); this type of selection is very common. Negative assortative mating is the opposite case, when people avoid mating with…

  • positive beta decay

    beta decay: In positron emission, also called positive beta decay (β+-decay), a proton in the parent nucleus decays into a neutron that remains in the daughter nucleus, and the nucleus emits a neutrino and a positron, which is a positive particle like an ordinary electron in mass but…

  • positive beta-particle decay

    beta decay: In positron emission, also called positive beta decay (β+-decay), a proton in the parent nucleus decays into a neutron that remains in the daughter nucleus, and the nucleus emits a neutrino and a positron, which is a positive particle like an ordinary electron in mass but…

  • positive charge imbalance (solid-state physics)

    Hole, in condensed-matter physics, the name given to a missing electron in certain solids, especially semiconductors. Holes affect the electrical, optical, and thermal properties of the solid. Along with electrons, they play a critical role in modern digital technology when they are introduced into

  • positive clutch (device)

    clutch: Positive clutches are collars with jaws that interlock, one member being rigidly attached to its shaft while the other slides on its shaft.

  • positive displacement pump

    pump: Positive displacement pumps.: Positive displacement pumps, which lift a given volume for each cycle of operation, can be divided into two main classes, reciprocating and rotary. Reciprocating pumps include piston, plunger, and diaphragm types; rotary pumps include gear, lobe, screw, vane, and cam pumps.

  • positive economics

    economics: Methodological considerations in contemporary economics: …wont to distinguish between “positive economics” and “normative economics.” Positive economics seeks to establish facts: If butter producers are paid a subsidy, will the price of butter be lowered? Will a rise in wages in the automotive industry reduce the employment of automobile workers? Will the devaluation of currency…

  • positive electron (subatomic particle)

    Positron, positively charged subatomic particle having the same mass and magnitude of charge as the electron and constituting the antiparticle of a negative electron. The first of the antiparticles to be detected, positrons were discovered by Carl David Anderson in cloud-chamber studies of the

  • positive eugenics (genetics)

    eugenics: Early history: …leading to terms such as positive eugenics, defined as promoting the proliferation of “good stock,” and negative eugenics, defined as prohibiting marriage and breeding between “defective stock.” For eugenicists, nature was far more contributory than nurture in shaping humanity.

  • positive externality (economics)

    environmental economics: Market failure: Positive externalities also result in inefficient market outcomes. However, goods that suffer from positive externalities provide more value to individuals in society than is taken into account by those providing the goods. An example of a positive externality can be seen in the case of…

  • positive feedback (electronics)

    electronics: Oscillation: If feedback is positive, the feedback signal reinforces the original one, and an amplifier can be made to oscillate, or generate an AC signal. Such signals are needed for many purposes and are created in numerous kinds of oscillator circuits. In a tunable oscillator, such as that required…

  • positive film (photography)

    history of photography: Colour photography: With this reversal (slide) film, colour transparencies could be obtained that were suitable both for projection and for reproduction. A year later the Agfa Company of Germany developed the Agfacolor negative-positive process, but owing to World War II the film did not become available until 1949. Meanwhile,…

  • positive freedom (philosophy)

    philosophical anthropology: The idealism of Kant and Hegel: …the English-speaking world against the “positive” freedom that supposedly accrues to individual human beings through their identification with institutions and traditions of thought and practice. This kind of freedom is unfavourably contrasted with the “negative” freedom that is, in essence, the ability and the right to say “no,” and to…

  • positive hole (solid-state physics)

    Hole, in condensed-matter physics, the name given to a missing electron in certain solids, especially semiconductors. Holes affect the electrical, optical, and thermal properties of the solid. Along with electrons, they play a critical role in modern digital technology when they are introduced into

  • positive ion (chemistry)

    Cation, atom or group of atoms that bears a positive electric charge. See

  • positive law (international law)

    Cornelis van Bynkershoek: …helped develop international law along positivist lines.

  • positive modulation (biochemistry)

    metabolism: Positive modulation: Not all pacemaker enzymes are controlled by inhibition of their activity. Instead, some are subject to positive modulation—i.e., the effector is required for the efficient functioning of the enzyme. Such enzymes exhibit little activity in the absence of the appropriate allosteric effector. One…

  • positive on glass (photography)

    tintype: …essentially a variation on the ambrotype, which was a unique image made on glass, instead of metal. Just as the ambrotype was a negative whose silver images appeared grayish white and whose dark backing made the clear areas of shadows appear dark, so the tintype, actually negative in its chemical…

  • positive organ (musical instrument)

    Positive organ , (from Latin ponere: “to place”), in Western music, small organ used in liturgical and, at times, in secular music from the 10th to the 17th century. It had short legs and was set on a table or the floor; two persons with a cart could move it. Two persons were also needed to operate

  • Positive Philosophy of Auguste Comte, The (work by Comte)

    Auguste Comte: Life: …philosophy in a work entitled Cours de philosophie positive (1830–42; “Course of Positive Philosophy”; Eng. trans. The Positive Philosophy of Auguste Comte).

  • positive political theory (political science and economics)

    Rational choice theory, school of thought based on the assumption that individuals choose a course of action that is most in line with their personal preferences. Rational choice theory is used to model human decision making, especially in the context of microeconomics, where it helps economists

  • positive pressure ventilator (machine)

    polio: Treatment and vaccination: …mechanical aids such as the positive pressure ventilator, which pumps air into the patient’s lungs through an endotracheal tube inserted into the windpipe. Ventilators have largely replaced the “iron lungs” that gave polio such a dreadful image during the 20th century. Formally known as tank respirators, iron lungs were large…

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