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Perigord ... permit

Perigord: historic and cultural region encompassing the southern French departement of Dordogne and part of Lot-et-Garonne and roughly coextensive with the former county of Perigord. The area was originally inhabited by the Gallic tribe of the Petrocorii, or Petragorici, whose capital ...
Perigordian industry: tool tradition of prehistoric men in Upper Paleolithic Europe that followed the Mousterian industry, was contemporary in part with the Aurignacian, and was succeeded by the Solutrean. Perigordian tools included denticulate (toothed) tools of the type used earlier in the ...
Perigueux: town, departement of Dordogne, Aquitaine region, southwestern France. An episcopal see, it lies on the right bank of the Isle River, east-northeast of Bordeaux and southwest of Paris. Originally settled by a Gaulish tribe, the Petrocorii, the town fell to ...
Perija, Mountains of: mountain chain, the northward extension of the Andean Cordillera Oriental, forming part of the border between Colombia and Venezuela. The range extends for 190 miles (306 km) from the vicinity of Ocana, Colombia, northward to the Guajira Peninsula. Its crest ...
perilla oil: drying oil obtained from the seeds of Asiatic mint plants of the genus Perilla. Perilla oil is used along with synthetic resins in the production of varnishes. Perilla oil dries in less time than linseed oil and on drying forms ...
Perim Island: island in the Strait of Mandeb off the southwestern coast of Yemen, to which it belongs. A rocky volcanic island, lying just off the southwestern tip of the Arabian Peninsula, Perim is 5 square miles (13 square km) in area ...
period: in geology, the basic unit of the geologic time scale; during these spans of time specific systems of rocks were formed. Originally, the sequential nature of defining periods was a relative one, originating from the superposition of corresponding stratigraphic sequences ...
period: in music, unit of melodic organization made up of several related consecutive phrases. Often the period has two phrases, typically of 8 or, in some cases, 16 measures each. The first phrase, called the antecedent, ends on a semi- or ...
periodic law: in chemistry, the generalization that there is a recurring pattern in the properties of the elements when they are arranged in order of increasing atomic number-i.e., the total number of protons in the atomic nucleus. The periods ...
periodic motion: in physics, motion repeated in equal intervals of time, the time of each interval being called the period. Periodic motion is performed, for example, by a rocking chair, a bouncing ball, a vibrating tuning fork, a swing in motion, the ...
periodical: a journal or other publication whose issues appear at fixed or regular intervals. See magazine; newspaper.
periodontal membrane: fleshy tissue between tooth and tooth socket that holds the tooth in place, attaches it to the adjacent teeth, and enables it to resist the stresses of chewing. It develops from the follicular sac that surrounds the embryonic tooth during ...
periodontics: dental specialty concerned with the prevention, diagnosis, and treatment of functional and structural diseases of the periodontal membrane and related tissues that surround and support the teeth. Degeneration or inflammation of these tissues can be caused by various systemic or ...
periodontitis: inflammation of the soft tissues around the teeth, characterized by swollen, tender gums and eventual loss of teeth. Periodontitis begins with the deposition of bacterial plaque on the teeth below the gum line, irritating and eroding the neighbouring tissues. At ...
periosteum: dense fibrous membrane covering the surfaces of bones, consisting of an outer, fibrous layer and an inner, cellular layer. The outer layer is composed mostly of collagen and contains nerve fibres that cause pain when the tissue is damaged. It ...
peripeteia: the turning point in a drama after which the plot moves steadily to its denouement. It is discussed by Aristotle in the Poetics as the shift of the tragic protagonist's fortune from good to bad, which is essential to the ...
periphrasis: the use of a longer phrasing in place of a possible shorter form of expression; a roundabout or indirect manner of writing or speaking. In literature periphrasis is sometimes used for comic effect, as illustrated by Charles Dickens in the ...
periscope: optical instrument used in land and sea warfare, submarine navigation, and elsewhere to enable an observer to see his surroundings while remaining under cover, behind armour, or submerged.
perissodactyl: any member of the order Perissodactyla, a group of herbivorous mammals characterized by the possession of either one or three hoofed toes on each hindfoot. They include the horses, asses, and zebras, the tapirs, and the rhinoceroses. The name (Greek ...
peristalsis: involuntary movements of the longitudinal and circular muscles, primarily in the digestive tract but occasionally in other hollow tubes of the body, that occur in progressive wavelike contractions. Peristaltic waves occur in the esophagus, stomach, and intestines. The waves can ...
peristerite: iridescent gemstone in the plagioclase (q.v.) series of feldspar minerals. The name (from Greek peristera, "pigeon") refers to the resemblance of fine specimens such as those from Ontario and Quebec to the commonly iridescent feathers of a pigeon's neck. In ...
peritoneum: large membrane in the abdominal cavity that connects and supports internal organs. It is composed of many folds that pass between or around the various organs. Two folds are of primary importance: the omentum, which hangs in front of the ...
peritonitis: inflammation of the peritoneum, the membrane that lines the abdominal wall and then folds in to enclose the abdominal organs. The condition is marked by an accumulation of cells, pus, and other bodily fluids, such as serum and fibrin, in ...
peritrich: any ciliated vase-shaped protozoan of the order Peritrichida (more than 1,000 species), found in both fresh and salt water. Usually nonmotile (sessile), they attach themselves to underwater objects, but a few genera, such as Telotrochidium, are free-swimming. In most peritrichs ...
periwinkle: in botany, any of various plants of the genus Vinca of the dogbane family (Apocynaceae). The name periwinkle is possibly taken from pervinka, the Russian name of the flower, which in turn is derived from pervi, "first," as it is ...
periwinkle: in zoology, any small marine snail belonging to the family Littorinidae. Periwinkles are widely distributed shore (littoral) snails, chiefly herbivorous, usually found on rocks, stones, or pilings between high- and low-tide marks; a few are found on mud flats, and ...
Periyar: river and lake in southern Kerala state, southwestern India. The river, 140 mi (225 km) long, rises in the Western Ghats range near the border with Tamil Nadu state and flows north to Periyar Lake in Kottayam district. The lake, ...
Periyar Wild Life Sanctuary: wildlife preserve in Idukki district, Kerala state, southern India. The sanctuary is noted for herds of elephants, sometimes numbering 50 members. In addition, bonnet monkey, nilgai, langur, porcupine, sloth bear, tiger, leopard, Asian elephant, barking deer, gray jungle fowl, kingfisher, ...
perjury: willful, knowing, and corrupt giving under oath of false testimony regarded as material to the issue or point of inquiry. All elements of the crime are essential for conviction. Criminal intent is required; a person who makes a false statement ...
Perkin, Sir William Henry: British chemist who discovered aniline dyes.
Perkins, Anthony: American actor who was best remembered for his portrayal of murderous motel owner Norman Bates in the Alfred Hitchcock thriller Psycho (1960); he reprised this role in three sequels (1983, 1986, and 1990).
Perkins, Carl: American singer, songwriter, and guitarist whose song "Blue Suede Shoes" was a touchstone of the rockabilly musical movement of the 1950s. A "triple threat" performer-a strong singer, a prolific and imaginative songwriter, and an excellent and influential lead guitarist-Perkins rose ...
Perkins, Frances: U.S. secretary of labor during the presidency of Franklin D. Roosevelt. Besides being the first woman to be appointed to a cabinet post, she also served one of the longest terms of any Roosevelt appointee (1933-45).
Perkins, George Walbridge: U.S. insurance executive and financier who organized the health insurance agency system and the corporate structures of several large companies. He also served as chairman of Theodore Roosevelt's Progressive Party, organizing Roosevelt's 1912 presidential campaign.
Perkins, Jacob: American inventor who produced successful innovations in many fields.
Perkins, Lucy Fitch: American writer of children's books, best remembered for her Twins series of storybooks that ranged in setting among different cultures and times.
Perkins, Maxwell: influential American editor who discovered many of the most prominent American writers of the first half of the 20th century.
Perkons: sky deity of Baltic religion, renowned as the guardian of law and order and as a fertility god. The oak, as the tree most often struck by lightning, is sacred to him. Perkons is related in functions and image to ...
Perl, Martin Lewis: American physicist who received the 1995 Nobel Prize for Physics for discovering a subatomic particle that he named the tau, a massive lepton with a negative charge. The tau, which he found in the mid-1970s, was the first evidence of ...
perlite: a natural glass with concentric cracks such that the rock breaks into small, pearllike bodies. It is formed by the rapid cooling of viscous lava or magma. Perlite has a waxy to pearly lustre and is commonly gray or greenish ...
Perlman, Itzhak: Israeli-born violinist known for a brilliant virtuoso technique. His refinement of detail led many to regard him as one of the finest performers of the major violin repertoire of his time.
Perm: city and administrative centre of Perm oblast (province), western Russia. The city stands on both banks of the Kama River below its confluence with the Chusovaya.
Perm: oblast (province), western Russia. It occupies an area on the western flank of the central Ural Mountains, extending from the crestline in the east across the broad basin of the middle Kama River. The northwest corner of the oblast is ...
permafrost: perennially frozen ground, a naturally occurring material with a temperature colder than 0° C (32° F) continuously for two or more years. Such a layer of frozen ground is designated exclusively on the basis of temperature. Part or all of ...
Permalloy: trademark of the Western Electric Company for nickel-iron alloys having much higher magnetic permeability than iron alone. It is widely used for fabricating the thin pieces that are laminated to form transformer cores. The proportion of nickel may range from ...
permeability: capacity of a porous material for transmitting a fluid; it is expressed as the velocity with which a fluid of specified viscosity, under the influence of a given pressure, passes through a sample having a certain cross section and thickness. ...
Permeke, Constant: painter and sculptor, who was significant in the development of Expressionism in Belgium.
Permian Basin: large sedimentary basin in western Texas and southeastern New Mexico that is noted for its rich petroleum and natural-gas deposits. It originated as a marine basin bordered by extensive deltas during the Permian and Triassic periods (between 286 and 208 ...
Permian Period: last period of the Paleozoic Era. It began about 286 million years ago and ended 245 million years ago, extending from the close of the Carboniferous to the outset of the Triassic (see ). The Permian is often divided into ...
Permic languages: division of the Finno-Ugric branch of the Uralic language family, consisting of the Udmurt (Votyak), Komi (Zyryan), and Permyak (Komi-Permyak) languages. The Permic languages are spoken along the northern and western reaches of the Ural Mountains in Russia in and ...
permit: marine fish, a species of pompano (q.v.).