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acromegaly ... Adams

acromegaly: growth and metabolic disorder characterized by enlargement of the skeletal extremities. It is the result of overproduction of pituitary growth hormone (somatotropin) after maturity, caused by a tumour of the ...
acropolis: (Greek: "city at the top"), central, defensively oriented district in ancient Greek cities, located on the highest ground and containing the chief municipal and religious buildings. Because the founding of ...
Acropolites, George: Byzantine scholar and statesman, the author of Chronike Syngraphe ("Written Chronicle"), a history of the Byzantine Empire from 1203 to 1261. He also played a major diplomatic ...
acrostic: short verse composition, so constructed that the initial letters of the lines, taken consecutively, form words. The term is derived from the Greek words akros, "at the end," and stichos,"line," ...
acroterion: in architecture, decorative pedestal for an ornament or statue placed atop the pediment of a Greek temple; the term has also been extended to refer to the statue or ornament ...
acrylic compound: any of a class of synthetic plastics, resins, and oils used to manufacture many products. By varying the starting reagents and the process of forming, a material may be produced ...
acrylic painting: painting executed in the medium of synthetic acrylic resins. Acrylics dry rapidly, serve as a vehicle for any kind of pigment, and are capable of giving both the transparent brilliance ...
Act of Parliament clock: plain, hanging, weight-driven wall clock with a large wooden, painted or lacquered dial. The term Act of Parliament clock was applied incorrectly to these timepieces, which were thought to have ...
Acta: (Latin: "Acts"), in ancient Rome, minutes of public business and gazette of political and social events. They were in two forms: Acta Senatus and Acta diurna.
Actaeon: in Greek mythology, son of the god Aristaeus and Autonoe (daughter of Cadmus, the founder of Thebes in Boeotia); he was a Boeotian hero and hunter. According to Ovid's Metamorphoses, ...
actin: protein that is an important contributor to the contractile property of muscle and other cells. It exists in two forms: G-actin (monomeric globular actin) and F-actin (polymeric fibrous actin), the ...
acting: the performing art in which movement, gesture, and intonation are used to realize a fictional character for the stage, for motion pictures, or for television.
actinide element: any of a series of 15 consecutive chemical elements in the periodic table from actinium to lawrencium (atomic numbers 89-103). As a group they are significant largely because of their ...
actinium: (Ac), radioactive chemical element, in Group IIIb of the periodic table, atomic number 89. Actinium was discovered (1899) by Andre-Louis Debierne in pitchblende residues left after Pierre and Marie Curie ...
actinium series: set of unstable heavy nuclei constituting one of the four radioactive series (q.v.).
actinolite: an amphibole mineral in the tremolite-actinolite-ferrotremolite series of calcium, magnesium, and iron silicates. The minerals in this series are abundant in regionally metamorphosed rocks, such as schists. Tremolite may weather ...
actinometer: in chemistry, a substance or a mixture of substances that reacts through the action of light and that, because of the easily determined quantitative relationship between the extent of the ...
actinomycete: any member of a heterogeneous group of gram-positive, generally anaerobic bacteria noted for a filamentous and branching growth pattern that results, in most forms, in an extensive colony, or mycelium. ...
actinomycosis: a noncontagious bacterial infection of humans and cattle that is caused by two anaerobic species of the genus Actinomyces. The disease is characterized by multiple painful, hard swellings filled with ...
actinomyxidian: any parasitic microorganism of the class Actinomyxidia (Actinosporea), phylum Myxosporidia (Myxospora). It inhabits the alimentary canal of certain aquatic worms. The characteristic spores develop in the host's gut after the ...
action: in theoretical physics, an abstract quantity that describes the overall motion of a physical system. Motion, in physics, may be described from at least two points of view: the close-up ...
Action Francaise: (French: "French Action"), influential right-wing antirepublican group in France during the first 40 years of the 20th century. Action Francaise was also the name of a daily newspaper (published from ...
Action painting: direct, instinctual, and highly dynamic kind of art that involves the spontaneous application of vigorous, sweeping brushstrokes and the chance effects of dripping and spilling paint onto the canvas. The ...
action potential: the brief (about one-thousandth of a second) reversal of electric polarization of the membrane of a nerve cell (neuron) or muscle cell. In the neuron an action potential produces the ...
Actium, Battle of: (September 2, 31 BC), naval battle off a promontory in the north of Acarnania, on the western coast of Greece, where Octavian (known as the emperor Augustus after 27 BC), ...
activated-sludge method: sewage-treatment process in which sludge, the accumulated, bacteria-rich deposits of settling tanks and basins, is seeded into incoming waste water and the mixture agitated for several hours in the presence ...
activation: in psychology, the stimulation of the cerebral cortex into a state of general wakefulness, or attention. Activation proceeds from various portions of the brain, but primarily from the reticular formation, ...
activation energy: in chemistry, the minimum amount of energy that is required to activate atoms or molecules to a condition in which they can undergo chemical transformation or physical transport. In terms ...
activity: in radioactive-decay processes, the number of disintegrations per second, or the number of unstable atomic nuclei that decay per second in a given sample. Activity is determined by counting, with ...
activity coefficient: in chemistry, the ratio of the chemical activity of any substance to its molar concentration. The measured concentration of a substance may not be an accurate indicator of its chemical ...
Acto Adicional of 1834: amendment to the Brazilian constitution of 1824 that abolished some of that charter's extremely centralist and authoritarian aspects. It was enacted as a concession to federalists and republicans who threatened ...
Acton, John Emerich Edward Dalberg Acton, 1st Baron, 8th Baronet: English Liberal historian and moralist, the first great modern philosopher of resistance to the evil state, whether its form be authoritarian, democratic, or socialist. A comment that he wrote in ...
Acton, Sir John Francis Edward, 6th Baronet: commander of the naval forces of Tuscany and then of Naples who as prime minister of Naples allied that kingdom with England and Austria in the period of the French ...
actor-manager system: method of theatrical production dominant in England and the U.S. in the 19th century, consisting of a permanent company formed by a leading actor who chose his own plays, took ...
Actors Studio, The: prestigious professional actors' workshop in New York City whose members have been among the most influential performers in American theatre and film since World War II. It is one of ...
Acts of the Apostles, The: fifth book of the New Testament, a valuable history of the early Christian church. Acts was written in Greek, presumably by the Evangelist Luke, whose gospel concludes where Acts begins, ...
actuary: one who calculates insurance risks and premiums. Actuaries compute the probability of the occurrence of various contingencies of human life, such as birth, marriage, sickness, unemployment, accidents, retirement, and death. ...
Acuff, Roy: American vocalist, songwriter, and fiddle player, called the "King of Country Music," who in the mid-1930s reasserted the mournful musical traditions of Southeastern rural whites and became a national radio ...
Acuna, Rosario de: Spanish playwright, essayist, and short-story writer known for her controversial liberal views.
acupuncture: ancient Chinese medical technique for relieving pain, curing disease, and improving general health. It was devised before 2500 BC in China and by the late 20th century was used in ...
ad valorem tax: any tax imposed on the basis of the monetary value of the taxed item. Literally the term means "according to value." Traditionally, most customs and excises had "specific" rates; the ...
Ada: city, seat (1907) of Pontotoc county, south-central Oklahoma, U.S. It lies along Clear Boggy Creek, south of the Canadian River, and was named for the daughter of the first postmaster, ...
Ada group: ivory carvings and a group of about 10 illuminated manuscripts, dating from the last quarter of the 8th century, the earliest examples of the art of the Court School of ...
Adab: ancient Sumerian city located south of Nippur (modern Niffer or Nuffar), Iraq. Excavations (1903-04) carried out by the American archaeologist Edgar James Banks revealed buildings dating from as early as ...
adab: Islamic concept that became a literary genre distinguished by its broad humanitarian concerns; it developed during the brilliant height of 'Abbasid culture in the 9th century and continued through the ...
Adad: weather god of the Babylonian and Assyrian pantheon. The name Adad may have been brought into Mesopotamia toward the end of the 3rd millennium BC by Western (Amorite) Semites. His ...
adage: a saying, often in metaphoric form, that embodies a common observation, such as "If the shoe fits, wear it,'' "Out of the frying pan, into the fire,'' or "Early to ...
adah: (Arabic: "custom"), in Islamic law, a local custom that is given a particular consideration by judicial authorities even when it conflicts with some principle of canon law (Shari'ah); in Indonesia ...
Adair v. the United States: (1908), case in which the U.S. Supreme Court upheld "yellow dog" contracts forbidding workers from joining labour unions. William Adair of the Louisville and Nashville Railroad fired O.B. Coppage for ...
Adair, John: Scottish surveyor and cartographer whose maps established a standard of excellence for his time and probably inspired the early 18th-century surveys of Scotland. Between 1680 and 1686 he completed maps ...
Adal: historic Islamic state of eastern Africa, in the Danakil-Somali region southwest of the Gulf of Aden, with its capital at Harer (now in Ethiopia). Its rivalry with Christian Ethiopia began ...
Adalbero Of Ardennes: archbishop of Reims who, by declaring the Frankish crown to be elective rather than hereditary, paved the way for the accession of Hugh Capet in place of the Carolingian claimant, ...
Adalbert: Lombard king of Italy who shared the throne for 11 years with his father, Berengar II, and after Berengar's exile continued his father's struggle against the German king and Holy ...
Adalbert: German archbishop, the most brilliant of the medieval prince bishops of Bremen, and a leading member of the royal administration.
Adalbert, Saint: first bishop of Prague to be of Czech origin.
Adam and Eve: in the Judeo-Christian and Islamic traditions, the original human couple, parents of the human race.
Adam and Eve, Life of: pseudepigraphal work (a noncanonical writing that in style and content resembles authentic biblical works), one of many Jewish and Christian stories that embellish the account of Adam and Eve as ...
Adam Brothers: three French brothers who sculpted many monuments for the French and Prussian royal residences. They were exponents of a style that employed the textures of shells, corals, and perforated rocks. ...
Adam De La Halle: poet, musician, and innovator of the earliest French secular theatre.
Adam Of Bremen: German historian whose work on the archbishops of Hamburg-Bremen provides valuable information on German politics under the Salian emperors and is also one of the great books of medieval geography.
Adam's Bridge: chain of shoals, between the islands of Mannar, near northwestern Sri Lanka, and Rameswaram, off the southeastern coast of India. The bridge is 30 miles (48 km) long and separates ...
Adam's Peak: mountain in southwestern Sri Lanka (Ceylon), 7,360 feet (2,243 m) high and 11 miles (18 km) northeast of Ratnapura; it is located in the Sri Lanka hill country. Its conical ...
Adam, Adolphe: French composer whose music for the ballet Giselle (1841) is notable for its dramatic power. It has retained its popularity with dancers and audiences to the present day.
Adam, Paul: author whose early works exemplify the Naturalist and Symbolist schools and who later won considerable reputation for his historical and sociological novels. Publication of his first Naturalist novel, Chair molle ...
Adam, Robert: Scottish architect and designer who, with his brother James (1730-94), transformed Palladian Neoclassicism in England into the airy, light, elegant style that bears their name. His major architectural works include ...
Adamawa: state, northeastern Nigeria. It was administratively created in 1991 from the northeastern half of former Gongola state. Adamawa is bordered on the north and northwest by Borno and Bauchi states, ...
Adamawa: traditional emirate centred in what is now Adamawa state, eastern Nigeria. The emirate was founded by Modibbo Adama, who was one of Sheikh Usman dan Fodio's commanders and who began ...
Adamawa Plateau: volcanic upland in west-central Africa. Though chiefly in north-central Cameroon, part of the plateau, known as the Gotel Mountains, is in southeastern Nigeria. The plateau is the source of the ...
Adamawa-Ubangi languages: branch of the Niger-Congo language family consisting of 120 languages spoken by approximately 12 million people in an area that stretches from northeastern Nigeria across northern Cameroon, southern Chad, the ...
Adamic, Louis: novelist and journalist who wrote about the experience of American minorities, especially immigrants, in the early 1900s.
Adamkus, Valdas: Lithuanian American who was president of Lithuania from 1998 to 2003.
Adamnan, Saint: abbot and scholar, particularly noted as the biographer of St. Columba.
Adamnan, The Vision of: in the Gaelic literature of Ireland, one of the earliest and most outstanding medieval Irish visions. This graceful prose work dates from the 10th century and is preserved in the ...
Adamov, Arthur: avant-garde writer, a founder and major playwright of the Theatre of the Absurd.
Adams: town (township), Berkshire county, northwestern Massachusetts, U.S. It lies at the foot of Mount Greylock (3,491 feet [1,064 metres]), on the Hoosic River, 15 miles (24 km) north of Pittsfield. ...
Adams: county, southern Pennsylvania, U.S., mostly consisting of a piedmont region bordered by Maryland to the south and the Blue Ridge Mountains to the west and north. The principal waterways are ...