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Ishtar ... isotopic fractionation

Ishtar: in Mesopotamian religion, goddess of war and sexual love. Ishtar is the Akkadian counterpart of the West Semitic goddess Astarte. Inanna, an important goddess in the Sumerian pantheon, came to ...
Ishtar Gate: enormous burnt-brick entryway located over the main thoroughfare in the ancient city of Babylon (now in Iraq). Built about 575 BC, it became the eighth fortified gate in the city. ...
Ishtar Terra: the smaller of two continent-sized highland areas (terrae) on the planet Venus. Ishtar lies in Venus's northern hemisphere, extending from about latitude 45° N to 75° N and from about ...
Isidore Of Kiev: Greek Orthodox patriarch of Russia, Roman cardinal, Humanist, and theologian who strove for reunion of Greek and Latin Christendom but was forced into exile because of concerted opposition, particularly from ...
Isidore of Sevilla, Saint: theologian, last of the Western Latin Fathers, archbishop, and encyclopaedist, whose Etymologies, an encyclopaedia of human and divine subjects, was one of the chief landmarks in glossography ...
Isin: ancient Mesopotamian city, probably the origin of a large mound near Ad-Diwaniyah, in southern Iraq.
Isinglass: (foaled 1890), racehorse (Thoroughbred) who won the British Triple Crown in 1893 and earned a then record for a British horse of more than $235,000 (record broken in 1952) during ...
isinglass: thin sheets of mica, particularly of muscovite (q.v.).
Isis: one of the most important goddesses of ancient Egypt. Her name is the Greek form of an ancient Egyptian word that is perhaps associated with a word for "throne."
Iskandar Muda: sultan of Acheh (Atjeh) in northern Sumatra, under whom the region achieved its greatest territorial expansion and an international reputation as a centre of trade and of Islamic learning.
Iskandariyah, Al-: muhafazah (governorate), Lower Egypt. The muhafazah is densely settled in the north in and around its capital, Alexandria (Al-Iskandariyah); it includes a desert hinterland ...
Iskander, Fazil: Abkhazian author who wrote in Russian and used gentle humour to expose and satirize a variety of social ills.
Iskenderun: seaport and chief city of Iskenderun ilce (district), Hatay il (province), southern Turkey, located on the eastern shore of the Gulf of Iskenderun. It ...
Iskur River: longest river in Bulgaria, formed south of Samokov in the Rila Mountains by its headstreams, the Beli (White) Iskur and Cherni (Black) Iskur. It cuts a 40-mi (65-km) gorge through ...
Isla, Jose Francisco de: Spanish satirist and preacher noted for his novel known as Fray Gerundio.
Islam: major world religion belonging to the Semitic family; it was promulgated by the Prophet Muhammad in Arabia in the 7th century AD. The Arabic term islam, literally ...
Islam, Pillars of: the five duties incumbent on every Muslim: shahadah, the Muslim profession of faith; salat, or ritual prayer, performed in a prescribed manner five times ...
Islamabad: city, capital of Pakistan, on the Potwar Plateau, 9 miles (14 km) northeast of Rawalpindi, the former interim capital.
Islamic bath: public bathing establishment developed in countries under Islamic rule that reflects the fusion of a primitive Eastern bath tradition and the elaborate Roman bathing process. A typical bath house consists ...
Islamic caste: any of the units of social stratification that developed among Muslims in India and Pakistan as a result of the proximity of Hindu culture. Most of the South Asian Muslims ...
Islamic Conference, Organization of the: an Islamic organization established in Jeddah, Saudi Arabia, in May 1971, following summits by Muslim heads of state and government in 1969 and by Muslim foreign ministers in 1970. The ...
Islamic Development Bank: Muslim bank directed toward financing the economic and social development of members in accordance with the principles of the Shari'ah (Islamic sacred law). Conceived by the Organization of the Islamic ...
Islamic world: prehistory and history of the Islamic community.
island: any area of land smaller than a continent and entirely surrounded by water. Islands may occur in oceans, seas, lakes, ...
island arc: long, curved chain of oceanic islands associated with intense volcanic and seismic activity and orogenic (mountain-building) processes. Prime examples of this form of geologic feature include the Aleutian-Alaska Arc and ...
Islands, Bay of: bay of the South Pacific Ocean and geographic region, northern North Island, New Zealand, formed when the sea flooded an old river valley system. The bay has a shoreline of ...
Islay: most southerly island of the offshore Atlantic group known as the Inner Hebrides, in Argyll and Bute council area, historic county of Argyllshire, Scotland. It is separated from the island ...
Isle Royale: centre of a wilderness archipelago and the largest island in Lake Superior, northwestern Michigan, U.S. Administered as part of Keweenaw county, it lies 56 miles (90 km) from the Upper ...
Isley Brothers, the: American rhythm-and-blues and rock band that began recording in the late 1950s and continued to have hit records in the '60s and '70s. The original members were Kelly Isley (byname ...
Islington: inner borough of London, part of the historic county of Middlesex, located directly north of the City of London. It was established in 1965 by amalgamation of the former metropolitan ...
Isma'il: in full Isma'il Ibn Sharif second ruler of the 'Alawi dynasty of Morocco; his long reign (1672-1727) saw the consolidation of 'Alawi power, the development of an effective army trained ...
Isma'il I: shah of Iran (1501-24) and religious leader who founded the Safavid dynasty (first native dynasty to rule the kingdom in 800 years) and converted Iran from the Sunni to the ...
Isma'il I ibn Ahmad: (reigned 892-907), one of the Persian Samanid dynasty's most famous sovereigns, who was generous, brave, just, and cultivated. Originally governor of Transoxiana at the age of 21, he extended his ...
Isma'il Pasha: viceroy of Egypt under Ottoman suzerainty, 1863-79, whose administrative policies, notably the accumulation of an enormous foreign debt, were instrumental in leading to British occupation of Egypt in 1882.
Isma'il Shahid, Muhammad: Indian Muslim reformer who attempted to purge Indian Islam from idolatry and who preached holy war against the Sikhs and the British.
Isma'il, Ahmad: Egyptian field marshal who was Egypt's defense minister and commander in chief when he planned the attack across the Suez Canal that surprised Israel on October 6, 1973, and began ...
Isma'ilite: a sect of the Shi'ites (one of the major branches of Islam) that was most active as a religio-political movement in the 9th-13th century through its subsects, the Fatimids, the ...
Isma'iliyah, Al-: muhafazah (governorate), northeastern Nile delta, Lower Egypt. It is a square-shaped territory with a long, narrow extension northward along the Suez Canal, ending just south of Port Said. Its eastern ...
Ismail bin Dato' Abdul Rahman, Tun: Malay politician who held several ministerial portfolios.
Ismailia: capital of Al-Isma'iliyah muhafazah (governorate), northeastern Egypt. The city is about at the midpoint of the Suez Canal, on the northwestern shore of Lake At-Timsah. The lake, in a natural ...
Ismay, Hastings Lionel Ismay, Baron: British soldier who became Prime Minister Winston Churchill's closest military adviser during World War II and participated in most major policy decisions of the Allied powers.
isnad: (from Arabic sanad, "support"), in Islam, a list of authorities who have transmitted a report (hadith) of a statement, action, or approbation of Muhammad, one of his Companions (Sahabah), or ...
Iso-Hollo, Volmari: Finnish runner, who won two successive gold medals in the Olympic Games (1932, 1936) for the 3,000-metre steeplechase.
isobar: in nuclear physics, any member of a group of atomic or nuclear species all of which have the same mass number-that is, the same total number of protons and neutrons. ...
isobar: line on a weather map of constant barometric pressure drawn on a given reference surface. The isobaric pattern on a constant-height surface is extremely useful in weather forecasting because of ...
Isocrates: ancient Athenian orator, rhetorician, and teacher whose writings are an important historical source on the intellectual and political life of the Athens of his day. The school he founded differed ...
isocyanide: any of a class of organic compounds having the molecular structure R&singlehorzbond;N⁺ ≡ C, in which R is a combining group derived by removal of a hydrogen atom from an ...
isodrin: chlorine-containing organic compound used as an insecticide; see aldrin.
Isoko: people of the northwestern part of the Niger Delta in Nigeria, speaking a language of the Kwa branch of the Niger-Congo family. The term Sobo is used by ethnographers as ...
isolating language: a language in which each word form consists typically of a single morpheme. Examples are Classical Chinese (to a far greater extent than the modern Chinese languages) and Vietnamese. An ...
isolation: in medicine, separation of an infected individual (human or animal) from the healthy until that individual is no longer able to transmit the disease. In its strictest sense, the practice ...
isoleucine: an amino acid present in most common proteins, sometimes comprising 2 to 10 percent by weight. First isolated in 1904 from fibrin, a protein involved in blood-clot formation, isoleucine is ...
isomer: in nuclear physics, any of two or more nuclides (species of atomic nuclei) that consist of the same number of protons and the same number of neutrons but differ in ...
isomer: in meteorology, line on a map connecting points having the same monthly or seasonal precipitation, expressed as a percentage or fraction of the annual total; it is similar to an ...
isomerase: any one of a class of enzymes that catalyze reactions involving a structural rearrangement of a molecule. Alanine racemase, for example, catalyzes the conversion of L-alanine into its isomeric ...
isomerism: the existence of sets of two or more substances that have identical molecular formulas but different molecular structures or configurations, and hence different properties. The substances that make up these ...
isomerization: the chemical process by which a compound is transformed into any of its isomeric forms, i.e., forms with the same chemical composition but with different structure or configuration and, hence, ...
isometric drawing: method of graphic representation of three-dimensional objects, used by engineers, technical illustrators, and, occasionally, architects. The technique is intended to combine the illusion of depth, as in a perspective rendering, ...
isometric system: one of the crystal systems to which a given crystalline solid can be assigned. Crystals in this system are referred to three mutually perpendicular axes of equal lengths. If the ...
isoniazid: drug used in the treatment and prevention of tuberculosis. Isoniazid commonly is used in combination with other drugs, such as rifampin, ethambutol, pyrazinamide, or streptomycin; these drugs are used with ...
Isonzo, Battles of the: (1915-17), 12 battles along the Isonzo River on the eastern sector of the Italian Front in World War I.
isoperimetric problem: in mathematics, the determination of the shape of the closed plane curve having a given length and enclosing the maximum area (the curve is a circle). The calculus of variations ...
isopod: any member of the order Isopoda (class Crustacea), a group of diverse, widely occurring forms including marine, freshwater, and terrestrial species. Most are free-living, but a number of marine species ...
isoprene: a colourless, volatile liquid hydrocarbon obtained in processing petroleum or coal tar and used as a chemical raw material. The formula is C₅H₈.
isoprenoid: any of a class of organic compounds composed of two or more units consisting of five carbon atoms in a specific pattern. Isoprenoids play widely varying roles in the physiological ...
isopropyl alcohol: one of the most common members of the alcohol family of organic compounds. See propyl alcohol.
isorhythm: in music, the organizing principle of much of 14th-century French polyphony, characterized by the extension of the rhythmic texture (talea) of an initial section to the entire composition, despite the ...
isospin: property that is characteristic of families of related subatomic particles differing principally in the values of their electric charge. The families of similar particles are known as isospin multiplets: two-particle ...
Isospora: genus of parasitic protozoans of the sporozoan subclass Coccidia. Isospora causes the disease known as coccidiosis (q.v.) in humans, dogs, and cats. The species that attack humans, I. hominis and ...
isostasy: theoretical balance of all large portions of the Earth's crust as though they were floating on a denser underlying layer, about 110 km (70 miles) below the surface. Imaginary columns ...
Isotelus: genus of trilobites (extinct arthropods) restricted to Europe and North America during the Ordovician Period (505 to 438 million years ago). Isotelus was relatively large for a trilobite and was ...
isotherm: line drawn on a map or chart joining points with the same temperature. Sometimes the prefix choro- ("space") or chrono- ("time") is added. Isotherms are commonly used in meteorology to ...
isotone: any of two or more species of atoms or nuclei that have the same number of neutrons. Thus, chlorine-37 and potassium-39 are isotones, because the nucleus of this species of ...
isotope: one of two or more species of atoms of a chemical element with the same atomic number and position in the periodic table and nearly identical chemical behaviour but with ...
isotope dilution: radiochemical method of analysis for measuring the mass and quantity of an element in a substance. The procedure involves adding to a substance a known quantity of a radioisotope of ...
isotopic fractionation: enrichment of one isotope relative to another in a chemical or physical process. Two isotopes of an element are different in weight but not in gross chemical properties, which are ...