Pôrto Alegre
Pôrto Alegre (pop. 1,262,600), city in southeastern Brazil.
21st Century Webster's Family Encyclopedia - Pope to Proverbs, Book of
Po River
Po River, longest river in Italy.
Poerty
Poerty, shortage of income or resources necessary for a minimum standard of living in a particular society.
Popé
Popé (d. c.1692), medicine man of the Pueblo Indians who organized the so-called Pueblo Revolt in 1680 against the Spanish in New Mexico.
Pope
Pope, head of the Roman Catholic church and head of state of Vatican City. The pope is the bishop of Rome, successor in a long line that Roman Catholics believe began with St. Peter, the first bishop of Rome. Basing their authority upon Peter and, ultimately, upon the words of Jesus of Nazareth, the popes, as early as Clement I (c. 92–101), claimed paramount authority over all Christians an…
Alexander Pope
Pope, Alexander (1688–1744), the greatest English poet and satirist of the Augustan Age.
Poplar
Poplar, name of group of trees belonging to the willow family.
Popocatépetl
Popocatépetl, volcanic mountain in Mexico.
Sir Karl Raimund Popper
Popper, Sir Karl Raimund (1902–94), Austrian-born English philosopher, best known for his theory of falsification in the philosophy of science.
Poppy
Poppy, name for annual or herbaceous perennial plants of the genus Papaver and related genera.
Popular music
Popular music, term used to describe several kinds of music that are not classical.
Population
Population, number of or term for all the inhabitants of a designated territory. For the world as a whole, population doubled between 1930 and 1975, from 2 to 4 billion, and increased to 4.7 billion by mid-1983, with a possible 6 billion forecast for the year 2000. The sharpest increases have been in developing nations, which are least able to provide food, education, and jobs for all. Averting wo…
Populism
Populism, “grass roots” agrarian political movement incorporating a farmer-labor coalition.
Jean Baptiste Poquelin
Poquelin, Jean Baptiste See: Molie`re.
Porcelain
Porcelain, a kind of white earthenware.
Porcupine
Porcupine, name for large, spiny vegetarian rodents of two distinct families: Erithizontidae, confined to the Americas, and Hystricidae, to the tropics of the Old World.
Porcupinefish
Porcupinefish, slow-moving tropical fish that can blow up its body when alarmed.
Pore
Pore, minute opening of a gland in skin.
Porgy
Porgy, deep-bodied fish (family Sparidae) with powerful teeth.
Porifera
Porifera See: Sponge.
Pork
Pork, pig flesh used for food.
Pork barrel
Pork barrel, pejorative U.S. term for government spending on local, presumably unnecessary, projects.
Pornography
Pornography, term applied to materials, including books, pictures, magazines, and films, with obscene or offensive content designed to cause sexual excitement.
Porphyry
Porphyry (A.D. 233–304), ancient Greek philosopher, author of Introduction to the Categories, a book which discussed how the qualities of things could be put into categories and groups.
Porpoise
Porpoise, small toothed whale (family Phocaenidae), distinguished from dolphins in being smaller and having a rounded head with no projecting beaklike mouth.
Ferdinand Porsche
Porsche, Ferdinand See: Volkswagen.
Port
Port, sweet wine, usually red, fortified with brandy.
Port-au-Prince
Port-au-Prince (pop. 738,000), capital, largest city, and leading port of Haiti.
Port Authority of New York and New Jersey
Port Authority of New York and New Jersey, governing agency for port-owned facilities in New York City and adjacent New Jersey.
Port Elizabeth
Port Elizabeth (pop. 652,000), city in South Africa.
Port Louis
Port Louis (pop. 142,800), capital and largest city of the island nation of Mauritius.
Port Moresby
Port Moresby (pop. 145,300), capital and largest city of Papua New Guinea.
Port Said
Port Said (pop. 399,800), port city in Egypt.
Port-of-Spain
Port-of-Spain (pop. 51,100), capital and largest city of Trinidad and Tobago.
Port Sudan
Port Sudan (pop. 206,700), chief port city of Sudan.
Portage la Prairie
Portage la Prairie (pop. 13,198), city of southern Manitoba.
Portcullis
Portcullis See: Castle.
Porter
Porter, U.S. naval officers, father and son.
Cole Porter
Porter, Cole (1893–1964), U.S. popular song composer.
Fitz-John Porter
Porter, Fitz-John (1822–1901), U.S.
Katherine Anne Porter
Porter, Katherine Anne (1890–1980), U.S. short-story writer and novelist who won the 1966 Pulitzer Prize for her Collected Short Stories (1965).
William Sydney Porter
Porter, William Sydney See: Henry, O.
Portland
Portland (pop. 215,281), largest city in Maine.
Portland
Portland (pop. 445,400), largest city in Oregon, a leading West Coast port.
Portland cement
Portland cement See: Cement.
Porto
Porto, or Oporto (pop. 327,400), second largest city in Portugal.
Porto-Novo
Porto-Novo (pop. 144,000), capital and second largest city of Benin.
Portobelo
Portobelo (pop. 550), village in Panama.
Gaspar de Portolá
Portolá, Gaspar de (1723?–?84), Spanish colonizer of California.
Portsmouth
Portsmouth (pop. 187,900), major port and naval center in southern England.
Portsmouth
Portsmouth (pop. 26,254), New Hampshire, major seaport on the state's Atlantic coast.
Portugal
Portugal, republic on the Iberian peninsula in the extreme southwest of continental Europe. Excluding the Azores and Madeira, Portugal covers an area of 34,340 sq mi/88,941 sq km and is bordered by Spain to the east and north and by the Atlantic Ocean to the west and south. Portugal lies at the point where the western ridge of the high Spanish plateau slopes downward towards the Atlantic Ocean. Mo…
Portuguese
Portuguese, official language of Portugal and Brazil.
Portuguese Guinea
Portuguese Guinea See: Guinea-Bissau.
Portuguese man-of-war
Portuguese man-of-war (Physalia physalis), colorful jellyfish of the order Siphonophora.
Portuguese water dog
Portuguese water dog, web-footed dog capable of swimming great distances.
Portulaca
Portulaca, flower of the purslane family.
Poseidon
Poseidon, in Greek mythology, god of the sea.
Positivism
Positivism, philosophical theory of knowledge associated with the 19th-century French philosopher Auguste Comte.
Positron emission tomography
Positron emission tomography (PET), technique used to study brain activity.
Possum
Possum, tree-dwelling mammal of the family Phalangeridae, native to Australia and New Guinea.
Emily Price Post
Post, Emily Price (1872–1960), U.S. writer, accepted authority on correct social behavior because of her book Etiquette (1922).
Post mortem
Post mortem See: Autopsy.
Wiley Post
Post, Wiley (1899–1935), U.S. aviator.
U.S. Postal Service
Postal Service, U.S., independent federal agency that provides mail service nationwide.
Universal Postal Union
Postal Union, Universal (UPU), United Nations agency governing the international flow of mail.
Postimpressionism
Postimpressionism, term coined by critic Roger Fry to describe the work of certain painters (1880–90) whose styles, though dissimilar, flowed from, and were a reaction to, impressionism.
Pot
Pot See: Marijuana.
Potash
Potash, potassium-based salts used in fertilizers.
Potassium
Potassium, chemical element, symbol K; for physical constants see Periodic Table.
Potassium nitrate
Potassium nitrate See: Saltpeter.
Potato
Potato (Solarium tuberosum), herbaceous plant of the nightshade family, with an edible, fleshy, tuberous, underground stem.
Potato beetle
Potato beetle (Lema trilineata), destructive insect of the leaf beetle family.
Potato famine
Potato famine, in 19th-century Ireland, famine caused by potato blight.
Potawatomi
Potawatomi, North American tribe of the Algonquian language family.
Grigori Aleksandrovich Potemkin
Potemkin, Grigori Aleksandrovich (1729–91), Russian soldier and favorite of Catherine the Great.
electric Potential
Potential, electric, work done against electric fields in bringing a unit charge to a given point from some arbitrary reference point (usually earthed), measured in volts (i.e., joules per coulomb).
Potentiometer
Potentiometer, device used to obtain a precise measure of the electromotive force (emf), or voltage, of an electrical cell.
Potlatch
Potlatch, in many tribal cultures, especially among the Native Americans of the Northwest Coast, an elaborate ceremonial feast at which the host distributes or destroys his own wealth to gain status or office in his tribe.
Potomac River
Potomac River, U.S. river flowing through Washington, D.C.
Potsdam
Potsdam (pop. 142,300), city in eastern Germany, near Berlin.
Potsdam Conference
Potsdam Conference (July 17 to Aug. 2, 1945), a summit meeting at Potsdam, Germany, between Premier Joseph Stalin, President Harry S.
Beatrix Potter
Potter, Beatrix (1866–1943), English author and illustrator of children's books.
Pottery and porcelain
Pottery and porcelain, ceramic articles, especially vessels, made of clay (generally kaolin) and hardened by firing.
Potto
Potto (genus Perodicticus), various slow-moving African primates related to the lorises.
Francis Poulenc
Poulenc, Francis (1899–1963), French composer, member of the post-World War II group of composers called Les Six.
Poultry farming
Poultry farming, rearing of all types of domesticated farm fowls for eggs and flesh.
Ezra Loomis Pound
Pound, Ezra Loomis (1885–1972), U.S. poet, critic, and translator.
Roscoe Pound
Pound, Roscoe (1870–1964), U.S. jurist and educator who championed flexibility in the law and efficiency in court administration.
Nicolas Poussin
Poussin, Nicolas (1594–1665), greatest 17th-century French Baroque painter.
Powder metallurgy
Powder metallurgy, process of reducing metals into powder.
Powder River
Powder River, river of western United States.
Adam Clayton Powell Jr.
Powell, Adam Clayton, Jr. (1908–72), U.S. politician.
Anthony Dymoke Powell
Powell, Anthony Dymoke (1905– ), English novelist, best known for his contemporary comedy of manners A Dance to the Music of Time, a 12-volume series of novels starting with A Question of Upbringing (1951) and ending with Hearing Secret Harmonies (1976).
Colin Powell
Powell, Colin (1938– ), youngest person and first black officer ever to become Chair of the Joint Chiefs of Staff (1989–93), the highest-ranking military post in the United States.
John Wesley Powell
Powell, John Wesley (1834–1902), U.S. geologist and ethnologist best known for his geological and topographical surveys and for his anthropological studies of Native Americans.
Lewis Franklin Powell Jr.
Powell, Lewis Franklin, Jr. (1907– ), associate justice of the U.S.
Power
Power, in physics, the time rate at which work is done.
Power
Power, in the social sciences, the ability to exercise control over others.
Power
Power, in mathematics, the total of a number multiplied by itself a given number of times.
Power of attorney
Power of attorney, in U.S. law, legal document authorizing a person to act on behalf of the signatory, usually in business and financial matters.
Hiram Powers
Powers, Hiram (1805–73), U.S. sculptor.
Powhatan
Powhatan (c. 1550–1618), personal name Wahunsonacock, chief of the Powhatans and head of the Powhatan Confederacy of tribes, which he enlarged until it covered most of the Virginia tidewater region and part of Maryland.
Powhatan
Powhatan, North American tribe in eastern Virginia, of Algonquian linguistic stock.
Poznan
Poznan (pop. 1,300,000), city in Poland.
PR
PR See: Public relations.
Príncipe Island
Príncipe Island See: São Tomé and Principe.
Jacques Prévert
Prévert, Jacques (1900–77), French writer.
Antoine François Prévost d'Exiles
Prévost d'Exiles, Antoine François, or Abbé Prévost (1697–1763), French writer, priest, and adventurer.
Prado
Prado See: Madrid.
Praetor
Praetor, in ancient Rome (from 366 B.C.), a magistrate elected annually to administer justice, 2nd in rank to the consul.
Praetorian Guard
Praetorian Guard, elite household troops of the Roman emperors, consisting of 9 (later 10) cohorts of 1,000 foot soldiers with higher rank and pay than ordinary troops.
Pragmatic sanction
Pragmatic sanction, edict by a ruler pronouncing on an important matter of state, such as the succession.
Pragmatism
Pragmatism, philosophical method whose criterion of truth is relative to events and not, as in traditional philosophy, absolute and independent of human experience.
Prague
Prague, or Praha (pop. 1,214,200), capital and largest city of the Czech Republic, on the Vlatava River.
Prairie
Prairie, rolling grassland that once covered much of interior North America.
Prairie chicken
Prairie chicken, name for two species of grouse (genus Tympanuchus) that were once common in the eastern half of North America.
Prairie dog
Prairie dog, ground squirrel of the genus Cynomys.
Prairie Provinces
Prairie Provinces, popular name for the Canadian provinces of Manitoba, Saskatchewan, and Alberta.
Prairie wolf
Prairie wolf See: Coyote.
Praseodymium
Praseodymium, chemical element, symbol Pr; for physical constants see Periodic Table.
Prawn
Prawn See: Shrimp.
Praxiteles
Praxiteles (active c.370–330 B.C.), greatest Greek sculptor of his time.
Prayer book
Prayer book, collection of commonly used prayers in Judeo-Christian religious services.
Pre-Columbian art
Pre-Columbian art, art of what is now Latin America prior to Columbus' discovery of the Americas (1492).
Pre-emption
Pre-emption, right of individuals to purchase land or goods before others and the act of such purchases.
Pre-Socratic philosophy
Pre-Socratic philosophy, general term applied to the thought of the early Greek philosophers (c.600–400 B.C.) who lived before Socrates.
Edward Preble
Preble, Edward (1761–1807), U.S. naval officer.
Precambrian
Precambrian, whole of geological time from the formation of the planet Earth to the start of the Phanerozoic (the eon characterized by the appearance of abundant fossils in rock strata), thus lasting from about 4.55 billion to 570 million years ago.
Precipitation
Precipitation, in meteorology, all water particles that fall from clouds to the ground, including rain and drizzle, snow, sleet, and hail.
Predestination
Predestination, in theology, doctrine that through God's decree the souls of certain persons (the elect) are destined to be saved.
Pregnancy
Pregnancy, time between conception and birth.
Prehistoric animal
Prehistoric animal, animal that became extinct before human beings began to produce written records. Our knowledge of these animals is therefore derived almost completely from fossils. Although scientists believe life on earth began over 3 billion years ago, few fossils have been found that are more than 600 million years old. The earliest are all invertebrates, or animals without skeletal backbon…
Prehistoric people
Prehistoric people, general term for a variety of species of human ancestors. Humans and apes, who share common ancestors, began to diverge in their evolutionary development about 14 million years ago. The first certain ancestor of modern humans is Australopithecus afarensis, discovered in 1978, a species that flourished in Ethiopia and Tanzania 3.8–2.5 million years ago. Adult individuals …
Prejudice
Prejudice, opinions and attitudes formed by individuals or groups about other individuals or groups, usually without ample sustaining evidence.
Premature birth
Premature birth, birth of a baby before the 40th week of pregnancy.
Maurice Brazil Prendergast
Prendergast, Maurice Brazil (1859–1924), U.S. painter influenced by postimpressionism, a member of the ashcan school founded by 8 U.S. painters in 1908.
Presbyterian Church (U.S.A.)
Presbyterian Church (U.S.A.), largest Presbyterian denomination in the United States, formed in 1983 when the Presbyterian Church in the United States and the United Presbyterian Church in the U.S.A. were united.
Presbyterianism
Presbyterianism, form of Christian church government based on bodies of clergy and lay presbyters.
William Prescott
Prescott, William (1726–95), American Revolutionary colonel.
William Hickling Prescott
Prescott, William Hickling (1796–1859), U.S. historian.
President of the United States
President of the United States, elected official, head of the executive branch of the U.S. government. The office of president derives its authority from the U.S. Constitution. In order to avoid concentration and abuse of political power, the Constitution established a system of checks and balances whereby power in the U.S. government is divided among the Congress, an independent judiciary, and th…
Presidential libraries
Presidential libraries, collections of documents, personal papers, and other memorabilia of former U.S. presidents.
Presidential Medal of Freedom
Presidential Medal of Freedom See: Decorations, medals, and orders.
Presidential succession
Presidential succession, system of selecting a new U.S. president when the incumbent dies in office, resigns, is removed from office, or is unable to discharge his duties.
Elvis Presley
Presley, Elvis (1935–77), U.S. singer, first major rock star, and present-day cult hero.
Press
Press See: Journalism; Newspaper; Printing.
Pressburg
Pressburg See: Bratislava.
Pressure
Pressure, force acting on a surface per unit of area.
Prester John
Prester John, legendary Christian priest-king.
Pretoria
Pretoria (pop. 822,900), administrative capital of South Africa.
Andries Wilhelmus Jacobus Pretorius
Pretorius, Andries Wilhelmus Jacobus (1799–1853), commandant of the Boers and Great Trek leader.
Pretzel
Pretzel, popular snack biscuit.
André Previn
Previn, André (1929- ), German-born U.S. musician.
Pribilof Islands
Pribilof Islands, group of 4 small islands of volcanic origin in the Bering Sea, about 300 mi (483 km) southwest of Alaska.
Leontyne Price
Price, Leontyne (1927- ), U.S. soprano.
Prickly ash
Prickly ash, shrub or tree (Zanthoxylum americanum) growing in damp soils.
Prickly heat
Prickly heat, or heat rash, uncomfortable itching sensation caused by excessive sweating in hot weather.
Prickly pear
Prickly pear, any of a genus (Opuntia) of branching cactus with flat stems and yellow flowers.
Priest
Priest, in most religions, a cultic officer who communicates the sacred to the followers; a spiritual leader expert in ritual and generally the offerer of sacraments.
J(ohn) B(oynton) Priestley
Priestley, J(ohn) B(oynton) (1894–1984), English writer and critic.
Joseph Priestley
Priestley, Joseph (1733–1804), British theologian and chemist.
Primary color
Primary color See: Color.
Primary election
Primary election, in the United States, an election in which supporters of a political party elect candidates to run in a subsequent general election.
Primate
Primate, member of an order of mammals including humans, anthropoid apes, monkeys, tarsiers, pottos, galagos, and lemurs.
Prime meridian
Prime meridian, meridian that indicates zero degree longitude.
Prime minister
Prime minister, or premier, head of the government in a parliamentary system.
Prime minister of Canada
Prime minister of Canada, highest-ranking elected official of Canada and leader of the government.
Miguel Primo de Rivera
Primo de Rivera, Miguel (1870–1930), Spanish general and politician.
Primogeniture
Primogeniture, law by which the eldest son inherits all the lands of a family.
Primrose
Primrose, perennial plant (Primula officinalis) growing in dry meadows, lightly wooded areas, and along forest edges; the flowers, herb, and rootstock are used for medicinal purposes.
William Primrose
Primrose, William (1904–82), Scottish violist, U.S. resident from 1937.
Prince Albert
Prince Albert (pop. 33,700), city in central Saskatchewan.
Prince consort
Prince consort, husband of a reigning queen.
Prince Edward Island
Prince Edward Island, one of Canada's maritime provinces, and the smallest of all Canada's provinces both in area and population. Prince Edward Island is about 10 mi/16 km from the mainland, separated from it by the Northumberland Strait. The maximum length is about 145 mi/233 km and its greatest width about 55 mi/89 km. The shoreline is deeply serrated with tidal inlets. The surface…
Prince George
Prince George (pop. 67,600), city of central British Columbia.
Prince Rupert
Prince Rupert (pop. 15,800), port on the west coast of British Columbia.
Princeton
Princeton (pop. 25,718), borough and township in central New Jersey, site of Princeton University, Princeton Theological Seminary, and the Institute for Advanced Study.
Princeton University
Princeton University, private university in Princeton, N.J.
Printing
Printing, reproduction of words and pictures in ink on paper or other suitable media. Despite the advent of information retrieval systems, the storage and dissemination of knowledge are still based primarily on the printed word. Modern printing began with the work of Johann Gutenberg, who invented movable type and type metal in the 15th century. Individual characters could be used several times. T…
Prion
Prion, microscopic particle that produces a fatal disease in goats and sheep.
Prism
Prism, in geometry, a solid figure having 2 equal polygonal faces (the bases) lying in parallel planes and several others (the lateral faces) that are parallelograms.
Prison
Prison, institution for confining people convicted of breaking a law. There are three types of prisons in the United States: jails and lockups, run by city and county governments mainly for those awaiting trial; state prisons, operated by the individual states containing the majority of convicted criminals, and federal prisons, which house society's most violent offenders and those who brea…
Prisoners of war
Prisoners of war, combatant who has been captured by or has surrendered to an enemy state.
V(ictor) S(awdon) Pritchett
Pritchett, V(ictor) S(awdon) (1900–97), English novelist, short-story writer, and literary critic.
Right of Privacy
Privacy, Right of, customary right of a citizen to have a private life free of “undue” interference or publicity.
Privateer
Privateer armed vessel that was privately owned but commissioned by a government to prey upon enemy ships in wartime.
Privet
Privet, shrub whose dense growth makes it popular for hedges.
Privy Council
Privy Council, honorary group of appointed advisers to the reigning sovereign of Great Britain.
Probability
Probability, branch of mathematics that deals with the likelihood that an event will occur. Most commonly, the number of possible outcomes is counted, and the probability of any particular outcome is expressed as a fraction between 0 and 1. For instance, in rolling 2 dice there are 36 possible outcomes. Only one of these is that a 12 will turn up (a 6 on each die). The chance of rolling a 12 is th…
Probate
Probate, legal process of proving that a will is valid.
Probation
Probation, alternative to prison, whereby convicted offenders are placed under the supervision of a probation officer, on condition that they maintain good behavior.
Proboscis monkey
Proboscis monkey, large monkey (Nasalis larvatus) native to Borneo.
Procaine
Procaine, or novocaine, pain-killing drug used as an anesthetic.
Proclamation of
Proclamation of 1763, statement issued by the British government at the end of the French and Indian Wars, establishing territorial rights for North American Native Americans.
Profit
Profit, amount of money a company or individual engaged in business makes after all costs have been subtracted.
Profit sharing
Profit sharing, incentive developed by businesses and employers to give workers a share of the extra money a company makes.
Progeria
Progeria, or Hutchinson-Gilford syndrome, rare disease that causes premature aging in children and early death.
Progesterone
Progesterone, female sex hormone that causes changes in the womb lining necessary for the implantation of a fertilized egg.
Programmed learning
Programmed learning, teaching method whereby matter to be learned is arranged in a coherent sequence of small, clear steps (programmed), enabling the student to instruct, test, and, if necessary, correct him or herself at each step.
Progression
Progression, in mathematics, a sequence of numbers (terms) that have a direct relationship to one another.
Progressive Conservative Party
Progressive Conservative Party, one of Canada's two major political parties.
Progressive education
Progressive education, reform movement that grew from the idea that schooling should cater to the emotional as well as the intellectual development of the child and that the basis of learning should be the child's natural and individual curiosity, rather than an enforced discipline.
Progressive movement
Progressive movement, campaign for political, economic, and social reform in the United States, which began in the depression of the 1890s and ended in 1917 with U.S. involvement in World War I.
Progressive Party
Progressive Party, name of three 20th century U.S. political organizations. Each was largely characterized by programs of social and economic reform. The Progressive Party of 1912 (better known as the Bull Moose Party) chose ex-President Theodore Roosevelt as its nominee. It left the Republican Party after the nomination of William Taft, but they were reunited during the campaign of 1916. The Prog…
Prohibition
Prohibition, restriction or prevention of the manufacture and sale of alcoholic drinks.
Prohibition Party
Prohibition Party, minor U.S. political party.
Projector
Projector, machine that passes light through film to show pictures on a screen.
Aleksandr Mikhailovich Prokhorov
Prokhorov, Aleksandr Mikhailovich (1916- ), Soviet physicist awarded, with N.G.
Sergei Sergeyevich Prokofiev
Prokofiev, Sergei Sergeyevich (1891–1953), Russian composer who created a fierce, dynamic, unemotive style that later became somewhat softer and more eclectic.
Proletariat
Proletariat, name given to industrial employees as a social and economic class.
Prometheus
Prometheus, in Greek mythology, one of the Titans and a brother of Atlas.
Promethium
Promethium, chemical element, symbol Pm; for physical constants see Periodic Table.
Pronghorn
Pronghorn, resembling an antelope (Antilocapra americana) the only horned animal that sheds its horn sheath and the only one with branched horns as distinct from antlers.
Proofreading
Proofreading, reading and correcting of printed matter prior to publication.
Propaganda
Propaganda, selected information, whether true or false, designed to persuade people to adopt a particular belief, attitude, or course of action.
Propane
Propane See: Butane and propane.
Propeller
Propeller, mechanical device designed to impart forward motion, usually to a ship or airplane, operating on the screw principle.
Sextus Propertius
Propertius, Sextus (50?–16 B.C.), Roman elegiac poet, whose poems center on his love affair with his mistress Cynthia.
Property
Property, social concept and legal term indicating the ownership of, or the right to enjoy, something of value; it may also be an interest in something owned by another.
Property tax
Property tax, money collected by state and local governments from owners of property.
Prophet
Prophet, in the Old Testament of the Bible, a man who by special revelation proclaimed the word of God by oracles and symbolic actions; originally a seer or ecstatic.
Prophylaxis
Prophylaxis, general term for the prevention of diseases.
Proportion
Proportion, in mathematics, equality of two ratios.
Proportional representation
Proportional representation, system of electing members to a legislature in which political parties or groups contesting the election are awarded a number of seats in the legislature more or less proportional to the number of votes they get.
Proslavery movement
Proslavery movement, U.S. movement to justify and expand the practice of slavery prior to the Civil War.
Prospecting
Prospecting, process of searching for minerals worth exploiting economically.
Gabriel Prosser
Prosser, Gabriel (c. 1775–1800), black American slave who planned a slave revolt in Virginia, intending to create an independent black state and to become its king.
Prostaglandin
Prostaglandin, variety of naturally occuring aliphatic acids with various biological activities including increased vascular permeability, smooth muscle contraction, bronchial constriction, and alteration in the pain threshold.
Prostate gland
Prostate gland, male reproductive gland that surrounds the urethra at the base of the urinary bladder and that secretes prostatic fluid. This organ is formed of fibrous muscular and glandular tissue. It is described as having the shape of a chestnut and as being an inverted pyramid whose base is applied to the neck of the bladder. The normal gland usually measures about 1 in (2.54 cm) from front t…
Prosthetic
Prosthetic, mechanical or electrical device inserted into or onto the body to replace or supplement the function of a missing, defective, or diseased organ.
Prostitution
Prostitution, practice of exchanging sexual favors for material profit, usually money.
Protactinium
Protactinium, chemical element, symbol Pa; for physical constants see Periodic Table.
Protagoras
Protagoras (c.490–421 B.C.), Greek Sophist, remembered for the maxim “Man is the measure of all things.” A respected figure in Athens, where he spent most of life, he taught rhetoric and the proper conduct of life (“virtue”), and was appointed lawmaker to the Athenian colony of Thurii in 444 B.C.
Protective coloration
Protective coloration, adaptation of coloration by animals, often providing a means of defense against predators. Except where selection favors bright coloration for breeding or territorial display, most higher animals are colored in such a way that they blend in with their background: by pure coloration, by disruption of outline with bold lines or patches, or by a combination of the two. The most…
Protectorate
Protectorate, country that is nominally independent but surrenders part of its sovereignty, such as control over foreign policy, in return for protection by a stronger state.
Protein
Protein, high-molecular-weight compound that yields amino acid through hydrolysis. Although hundreds of different amino acids are possible, only 20 are found in appreciable quantities in proteins, and these are all alpha-amino acids. Proteins are found throughout all living organisms. Muscle, the major structural material in animals, is mainly protein; the 20% of blood that is not water is …
Protestant ethic
Protestant ethic, set of values that esteems hard work, thrift, duty, efficiency, and self-discipline.
Protestantism
Protestantism, principles of the Reformation.
Protista
Protista, members of a proposed group of organisms having characteristics of both the plant and the animal kingdoms.
Proton
Proton, elementary particle having a positive charge equivalent to the negative charge of the electron but possessing a mass approximately 1,837 times as great.
Protoplasm
Protoplasm, basic substance of which all living things are made up.
Protozoan
Protozoan, single-celled organism belonging to the phylum Protozoa.
Protractor
Protractor, semicircular device used to measure or to construct angles.
Pierre Joseph Proudhon
Proudhon, Pierre Joseph (1809–65), French social thinker.
Joseph Louis Proust
Proust, Joseph Louis (1754–1826), French chemist who established the law of definite proportions, or Proust's law.
Marcel Proust
Proust, Marcel (1871–1922), French novelist whose seven-part work Remembrance of Things Past is one of the greatest novels of the 20th century.
Provençal
Provençal, or langue d'oc, Romance language developed from the Latin spoken in southern France, principally Provence.
Provence
Provence, region and former province of France, embracing the lower Rhone River (including the Camargue) and the French Riviera.
Book of Proverbs
Proverbs, Book of, book of the Bible's Old Testament; an example of the “wisdom literature” popular in post-exilic Judaism.