• Ipomoea purpurea (plant)

    Ipomoea: Major species: Common morning glory (I. purpurea), an annual vine that bears heart-shaped leaves and purple, pink, or white flowers about 7 cm (3 inches) across, has become a troublesome weed in parts of southeastern North America. It is cultivated in many places.

  • Ipomoea quamoclit (plant)

    cypress vine, (Ipomoea quamoclit), tropical American twining climber naturalized in southern North America. It has star-shaped scarlet, pink, or white blooms amid deep green, deeply lobed leaves. It is a member of the morning glory family (Convolvulaceae) and is an annual. The closely related star

  • Ipomoea rubrocaerulea (plant)

    Ipomoea: Major species: Heavenly blue morning glory (I. violacea)—a twining perennial vine, usually cultivated as a garden annual—bears clusters of blue to purplish, sometimes white, flowers, 12 cm (4.7 inches) across, among heart-shaped leaves. It is native to tropical America. This vine bears seeds containing the alkaloids d-lysergic…

  • Ipomoea tricolor (plant)

    Ipomoea: Major species: Heavenly blue morning glory (I. violacea)—a twining perennial vine, usually cultivated as a garden annual—bears clusters of blue to purplish, sometimes white, flowers, 12 cm (4.7 inches) across, among heart-shaped leaves. It is native to tropical America. This vine bears seeds containing the alkaloids d-lysergic…

  • Ipomoea violacea (plant)

    Ipomoea: Major species: Heavenly blue morning glory (I. violacea)—a twining perennial vine, usually cultivated as a garden annual—bears clusters of blue to purplish, sometimes white, flowers, 12 cm (4.7 inches) across, among heart-shaped leaves. It is native to tropical America. This vine bears seeds containing the alkaloids d-lysergic…

  • IPPD (technology)

    aerospace industry: Design methods: …teams, is a method called integrated product and process development (IPPD). IPPD ensures that the needs of the users and those who bring the product to the customer through manufacturing and outside procurement are considered at the beginning of the design/build cycle. In cases in which maintenance plays a major…

  • Ippen (Japanese Buddhist monk)

    Buddhism: Pure Land: …up around the itinerant teacher Ippen. He traveled throughout Japan, advocating the chanting of Amida’s name at set intervals throughout the day; hence, his school was called the Ji (“Times”) school, or Jishū.

  • Ippen shōnin gyojo eden (Japanese art)

    Japanese art: Painting: …Hōnen shōnin eden and the Ippen shōnin gyojo eden present biographies of the priests Hōnen, founder of the Pure Land sect, and Ippen, beloved charismatic who founded an Amidist subgroup, the Ji sect. In vitality of defining brushwork, rich palette, and lavish depiction of the sundry details of contemporaneous existence,…

  • IPPF

    birth control: Family planning services: …toward creating what became the International Planned Parenthood Federation (IPPF).

  • Ippitsusai Bunchō (Japanese artist)

    Ippitsusai Bunchō was a Japanese artist in the ukiyo-e school, which depicted subjects drawn from everyday life. Ippitsusai studied with Ishikawa Yukimoto, a painter of the traditional Kanō school. He gained repute as a colourist, particularly in his painting of actors (nigeo-e, “portraits”). His

  • Ippolitov-Ivanov, Mikhail (Russian composer)

    Mikhail Ippolitov-Ivanov was a Russian composer of orchestral works and operas, of which the most popular were influenced by Caucasian and Georgian folk music. Ippolitov-Ivanov studied under Nikolay Rimsky-Korsakov at the St. Petersburg Conservatory and in 1882 became conductor of the symphony

  • Ippolitov-Ivanov, Mikhail Mikhaylovich (Russian composer)

    Mikhail Ippolitov-Ivanov was a Russian composer of orchestral works and operas, of which the most popular were influenced by Caucasian and Georgian folk music. Ippolitov-Ivanov studied under Nikolay Rimsky-Korsakov at the St. Petersburg Conservatory and in 1882 became conductor of the symphony

  • IPPP (chemical compound)

    isoprenoid: Biosynthesis of isoprenoids: …unknown compounds, mevalonic acid and isopentenyl pyrophosphate (IPPP), occur as important intermediates in the process.

  • iproniazid (drug)

    iproniazid, the first drug of the monoamine-oxidase inhibitor series to be introduced into medicine (1958). It was employed as an antidepressant until it was found to cause liver damage. Prior to its introduction as an antidepressant, iproniazid was studied as a drug similar in function to the

  • IPS (electronics)

    liquid crystal display: Other transmissive nematic displays: For example, in-plane switching (IPS) displays operate by applying a switching voltage to electrodes on a single substrate to untwist the liquid crystal. IPS displays have a viewing angle intrinsically superior to that of TFT TNs; however, the requirement for more electrode circuitry on their substrate can…

  • IPS (agency, Paraguay)

    Paraguay: Health and welfare: The state-run Institute of Social Provision (IPS) is funded by contributions from government, employers, and employees. It offers pensions, medical care, and subsidies during illness but reaches only a small percentage of the salaried workers.

  • iPS cell (biology)

    induced pluripotent stem cell (iPS cell), immature cell that is generated from an adult (mature) cell and that has regained the capacity to differentiate into any type of cell in the body. Induced pluripotent stem cells (iPS cells) differ from embryonic stem cells (ES cells), which form the inner

  • Ipsárion, Mount (mountain, Greece)

    Thasos: The highest mountain, Mount Ipsárion (3,947 feet [1,203 metres]), lies near the island’s northeastern coast. The population is distributed in about 10 villages, mostly at some distance from the sea; the chief town, Thásos (formerly Limín), is on the north coast.

  • ipsative measurement (psychology)

    ipsative measurement, type of assessment used in personality questionnaires or attitude surveys in which the respondent must choose between two or more equally socially acceptable options. Developed by American psychologist Paul Horst in the early 1950s, ipsative measurement tracks the progress or

  • Ipsen, Bodil (Danish actress)

    Bodil Ipsen was a Danish actress who, with her frequent stage partner, the character actor Poul Reumert, reilluminated the dramas of Henrik Ibsen and August Strindberg. Ipsen first appeared on the stage at the Royal Theatre, Copenhagen, in 1909. She showed wide versatility, achieving success in

  • Ipsilanti, Alexandru (Greek prince of Walachia)

    Romania: Between Turkey and Austria: …Constantin Mavrocordat abolished serfdom, and Alexandru Ipsilanti of Walachia (reigned 1774–82) initiated extensive administrative and legal reforms. Alexandru’s enlightened reign, moreover, coincided with subtle shifts in economic and social life and with the emergence of new spiritual and intellectual aspirations that pointed to the West and to reform.

  • Ipsos, Battle of (Mesopotamian history [301 bce])

    Alexander the Great’s sudden death in Babylon in 323 bce left his leading generals locked in decades of battling over the spoils of his empire. At the Battle of Ipsos in 301 bce, the Macedonian general Antigonus—long in the ascendant—was finally overpowered by the combined forces of his rivals, and

  • IPSP (biology)

    nervous system: Postsynaptic potential: …impulse, it is called an inhibitory postsynaptic potential (IPSP). The interaction of competing EPSPs and IPSPs at the hundreds or even thousands of synapses on a single neuron determines whether the nerve impulse arriving at the presynaptic terminals will be regenerated in the postsynaptic membrane.

  • Ipswich (Massachusetts, United States)

    Ipswich, town (township), Essex county, northeastern Massachusetts, U.S. It lies along the Ipswich River (there bridged since 1764), 28 miles (45 km) north-northeast of Boston. Settled in 1633 as Agawam, it was incorporated in 1634 and renamed for Ipswich, England. Lace making, the town’s first

  • Ipswich (district, England, United Kingdom)

    Ipswich: …Sea port town and borough (district), administrative and historic county of Suffolk, England. Located at the head of the Orwell estuary, in the southeastern part of the county, Ipswich is the county town (seat) and administrative center of Suffolk.

  • Ipswich (England, United Kingdom)

    Ipswich, North Sea port town and borough (district), administrative and historic county of Suffolk, England. Located at the head of the Orwell estuary, in the southeastern part of the county, Ipswich is the county town (seat) and administrative center of Suffolk. Ipswich prospered as a port for the

  • Ipswich Summer School of Art (school, Ipswich, Massachusetts, United States)

    Arthur Wesley Dow: He opened the Ipswich Summer School of Art in a house once owned by writer and Transcendentalist Ralph Waldo Emerson. The school, which he ran with his wife through 1907, offered classes in photography, painting, textiles, pottery, and other media. Among the well-known artists who studied there was…

  • Ipswich, Henry Fitzroy, Viscount (British noble)

    Henry Fitzroy, 1st duke of Grafton was the first duke of Grafton and the second illegitimate son of Charles II of England by Barbara Villiers, Duchess of Cleveland. After some initial hesitation he was officially recognized and became “the most popular and most able of the sons of Charles II.” He

  • Ipswichian Interglacial Stage (geochronology)

    Pleistocene Epoch: Glacial records: …last interglaciation, the Eemian and Ipswichian, are correlative with oxygen-18 stage 5e, and those of the last glaciation, the Weichselian and Devensian, correlate with oxygen-18 stages 5d–a, 4, 3, and 2. As in central North America, tills and other deposits are well known only from the last part of this…

  • IPTA (organization)

    Gulzar: Early life and influences: …Writers’ Association (PWA) and the Indian People’s Theatre Association (IPTA), respectively. In fact, it was in PWA meetings that he met Bollywood lyricist Shailendra, who introduced him to filmmaker Bimal Roy. About this time, Kalra also adopted the pen name Gulzar Deenvi (Gulzar meaning “a garden in bloom”; Deenvi for…

  • IPTO (United States military department)

    ARPANET: Roots of a network: …the first director of ARPA’s Information Processing Techniques Office (IPTO), the SAGE network demonstrated above all else the enormous power of interactive computing—or, as he referred to it in a seminal 1960 essay, of “man-computer symbiosis.” In his essay, one of the most important in the history of computing, Licklider…

  • IPU (international organization)

    Inter-Parliamentary Union (IPU), international organization of parliaments of sovereign states established in 1889 in Paris to promote representative democracy and world peace. The Nobel Prize for Peace was awarded eight times to leading personalities of the IPU in the organization’s early years

  • Ipueira (river, Brazil)

    São Francisco River: Physiography: …Francisco receives the São Pedro, Ipueira, and Pajeú rivers—culminates in the great Paulo Afonso Falls (see photograph). At the top of the falls, the river divides suddenly and violently and cuts three successive falls through the granite rocks for a total drop of about 275 feet. Below the falls the…

  • Ipuwer (Egyptian sage)

    Ipuwer, ancient Egyptian sage who is known because of the discovery of one poorly preserved manuscript relating his speech to the king and the royal court. Ipuwer’s manuscript, often called “The Admonitions of an Egyptian Sage,” is especially valuable for its commentary on woeful contemporary

  • IPV (medicine)

    John Franklin Enders: …to the development of the Salk vaccine for polio in 1954. Similarly, their production in the late 1950s of a vaccine against the measles led to the development of a licensed vaccine in the United States in 1963. Much of Enders’ research on viruses was conducted at the Children’s Hospital…

  • IPY

    Antarctica: IGY and the Antarctic Treaty: …at that time to organize similar programs every 50 years. In 1932–33 the Second International Polar Year took place, with 34 nations participating, but no Antarctic expeditions were mounted.

  • IQ (psychology)

    IQ, (from “intelligence quotient”), a number used to express the relative intelligence of a person. It is one of many intelligence tests. IQ was originally computed by taking the ratio of mental age to chronological (physical) age and multiplying by 100. Thus, if a 10-year-old child had a mental

  • ʿIqāb, Battle of Al- (Spanish history)

    Battle of Las Navas de Tolosa, (July 16, 1212), major battle of the Christian reconquest of Spain in which the Almohads (a Muslim dynasty of North Africa and Spain) were severely defeated by the combined armies of Castile, Aragon, Navarre, and Portugal. The battle was fought about 40 miles (64 km)

  • ʿiqāl (cord)

    keffiyeh: Variations: …thick black cord called the ʿiqāl is tied around the ghutrah to secure it to the head. This variation is worn primarily in the Gulf States, including Bahrain, Qatar, and the United Arab Emirates. In Iran the chafiyeh is worn atop the head and is typically checkered in a dark…

  • Iqaluit (Nunavut, Canada)

    Iqaluit, city, capital of Nunavut territory and headquarters of Baffin region, Canada. It lies at the head of Frobisher Bay, on southeastern Baffin Island. Iqaluit is the largest community in the eastern Canadian Arctic. It was established as a trading post in 1914 and became an air base during

  • īqāʿ (Islamic music)

    īqāʿāt , in Islamic music, rhythmic modes—i.e., patterns of strong, intermediate, and weak beats, separated by pauses of various lengths. A well-developed system of such modes was described by medieval theorists. Although six or eight basic modes are included in most treatises, many more have

  • īqāʿāt (Islamic music)

    īqāʿāt , in Islamic music, rhythmic modes—i.e., patterns of strong, intermediate, and weak beats, separated by pauses of various lengths. A well-developed system of such modes was described by medieval theorists. Although six or eight basic modes are included in most treatises, many more have

  • Iqbal (film by Kukunoor [2005])

    Girish Karnad: Acting and directing: …Heggadithi (1999) and acting in Iqbal (2005), Life Goes On (2009), and 24 (2016), among others.

  • Iqbal, Javed (Pakistani serial killer)

    Javed Iqbal was a Pakistani serial killer who murdered some 100 boys. His case attracted international attention not only because he was one of the deadliest serial killers in history but because, upon his conviction, he was sentenced to die in a manner similar to that in which he had tortured and

  • Iqbal, Muhammad (poet and philosopher)

    Muhammad Iqbal was a poet and philosopher known for his influential efforts to direct his fellow Muslims in British-administered India toward the establishment of a separate Muslim state, an aspiration that was eventually realized in the country of Pakistan. He was knighted in 1922. Iqbal was born

  • Iqbal, Sir Muhammad (poet and philosopher)

    Muhammad Iqbal was a poet and philosopher known for his influential efforts to direct his fellow Muslims in British-administered India toward the establishment of a separate Muslim state, an aspiration that was eventually realized in the country of Pakistan. He was knighted in 1922. Iqbal was born

  • IQF method (food processing)

    vegetable processing: Freezing: …a technology known as the individually quick-frozen (IQF) method. IQF is a method that does not allow large ice crystals to form in vegetable cells. Also, since each piece is individually frozen, particles do not cohere, and the final product is not frozen into a solid block. Various freezing techniques…

  • IQSY (international scientific program)

    Antarctica: Post-IGY research: …worldwide projects, such as the International Years of the Quiet Sun (1964–65), the International Biological Programme (1964–74), and the World Climate Research Programme (begun in 1980). It also advises the United Nations Framework Convention on Climate Change (UNFCCC) and the Intergovernmental Panel on Climate Change

  • iqṭāʿ (Islamic land grant)

    iqṭāʿ, in the Islāmic empire of the Caliphate, land granted to army officials for limited periods in lieu of a regular wage. It has sometimes been erroneously compared to the fief of medieval Europe. The iqṭāʿ system was established in the 9th century ad to relieve the state treasury when

  • Iqtiṣād fī al-lʿtiqād, al- (work by al-Ghazālī)

    al-Ghazālī: …Spanish), al-Iqtiṣād fī al-iʿtiqād (The Just Mean in Belief ), was probably written before he became a mystic, but there is nothing in the authentic writings to show that he rejected these doctrines, even though he came to hold that theology—the rational, systematic presentation of religious truths—was inferior to…

  • Iquan (Chinese pirate)

    Zheng Zhilong was a Chinese pirate leader who achieved great power in the transitional period between the Ming (1368–1644) and Qing (1644–1911/12) dynasties. As a boy, Zheng found employment with the Europeans in the Portuguese settlement at Macau, where he was baptized and given the Christian name

  • Iquique (Chile)

    Iquique, city, northern Chile. It is located on a rocky peninsula in the Atacama Desert, overlooking the Pacific Ocean. Its anchorage is protected from the open sea by the low, barren offshore island of Serrano, which is connected to the mainland by a stone causeway. Founded in the 16th century,

  • Iquique, Battle of

    Peru: The War of the Pacific (1879–83): At the Battle of Iquique (then in Peru, now in Chile), on May 21, 1879, the Peruvians suffered the loss of one of their best warships, the Independencia; then the Huáscar was captured on October 8, and this eventual surrender of control of the sea permitted a…

  • Iquitos (Peru)

    Iquitos, Amazon River port, northeastern Peru. It is located about 2,300 miles (3,700 km) upstream from the Atlantic Ocean and 640 miles (1,030 km) north-northeast of Lima. Iquitos is the capital of Peru’s Maynas province and the Loreto region, and it is the largest city in the Peruvian Amazon,

  • Ir (chemical element)

    iridium (Ir), chemical element, one of the platinum metals of Groups 8–10 (VIIIb), Periods 5 and 6, of the periodic table. It is very dense and rare and is used in platinum alloys. A precious, silver-white metal, iridium is hard and brittle, but it becomes ductile and can be worked at a white heat,

  • IR (chemical compound)

    polyisoprene: Cis-1,4 polyisoprene: Isoprene rubber (IR) is manufactured by the polymerization of synthetic isoprene, which is obtained from the thermal cracking of the naphtha fraction of petroleum. Polymerization is conducted in solution, using both anionic and Ziegler-Natta catalysts. The product is at most 98 percent cis-1,4 polyisoprene, and…

  • ʿIr Yizreʿel (Israel)

    ʿAfula, largest city of the Plain of Esdraelon, or Valley of Jezreel (Hebrew: ʿEmeq Yizreʿel), northern Israel. Named for the Arab village of Al-ʿAffūla formerly at that site, it is sometimes called ʿIr Yizreʿel (“City of Jezreel”). It was founded in 1925 on lands acquired by the American Zion

  • IR-8 (rice)

    Los Baños: …Research Institute, headquartered there, developed IR8, a high-yielding strain that significantly increased rice production. Pop. (2000) 82,027; (2010) 101,884.

  • IR8 (rice)

    Los Baños: …Research Institute, headquartered there, developed IR8, a high-yielding strain that significantly increased rice production. Pop. (2000) 82,027; (2010) 101,884.

  • IRA (Irish military organization)

    Irish Republican Army (IRA), republican paramilitary organization seeking the establishment of a republic, the end of British rule in Northern Ireland, and the reunification of Ireland. The IRA was created in 1919 as a successor to the Irish Volunteers, a militant nationalist organization founded

  • IRA (Russian company)

    Yevgeny Prigozhin: …a leadership role in the Internet Research Agency (IRA), a “troll farm” based in St. Petersburg responsible for a number of disinformation campaigns. The IRA spread false news, sowed division, and sought to shape political outcomes, most notably during the 2016 Brexit referendum in the United Kingdom and the 2016…

  • IRA Provos (Irish military organization)

    Irish Republican Army: …whereas the Provisionals, or “Provos,” believed that violence— particularly terrorism—was a necessary part of the struggle to rid Ireland of the British.

  • iraca (botany)

    Cyclanthaceae: Panama hat palm order of monocotyledonous flowering plants, which has 11 genera of mostly stemless, perennial, palmlike herbs, woody herbaceous shrubs, and climbing vines that are distributed in Central America and tropical South America.

  • irad-ı cedid (Ottoman treasury)

    Ottoman Empire: Selim III and the nizam-ı cedid: …entirely new treasury, called the irad-ı cedid (“new revenue”), whose revenues came from taxes imposed on previously untaxed sources and from the confiscation of some timars whose holders were not fulfilling their military and administrative duties to the state. Under the guidance of European technicians, factories were erected to manufacture…

  • Iradah-yi milli (political party, Iran)

    Sayyid Zia od-Din Tabatabaʾi: …the pro-British, anticommunist political party Iradah-yi milli (“The National Will”), which was active until 1951, at which time Tabatabaʾi faded from the political scene.

  • Iradier, Eduardo Dato (premier of Spain)

    Eduardo Dato Iradier was a Spanish statesman, leader of the Conservative Party from 1913 to 1921, and three-time premier. He instituted various reforms but proved unable to deal effectively with unrest or to heal the divisions within his party. As undersecretary in the Home Office in 1892 and as

  • Irakere (Cuban orchestra)

    Latin jazz: The Cuban orchestra Irakere was among the emblematic ensembles of this decade. Led by pianist Jesús (“Chucho”) Valdés (son of Bebo Valdés) and featuring soloists such as clarinetist-saxophonist Paquito D’Rivera and trumpeter Arturo Sandoval, the group was recognized for its innovative fusion of jazz, Western classical music, rock,…

  • Irákleio (Greece)

    Heraklion, largest city, a dímos (municipality), and principal port of the Greek island of Crete and capital of the pereferiakí enótita (regional unit) Heraklion (Irákleio). It lies on the island’s north coast along the Sea of Crete, just northwest of the ancient Minoan capital of Knossos. The

  • Iráklion (Greece)

    Heraklion, largest city, a dímos (municipality), and principal port of the Greek island of Crete and capital of the pereferiakí enótita (regional unit) Heraklion (Irákleio). It lies on the island’s north coast along the Sea of Crete, just northwest of the ancient Minoan capital of Knossos. The

  • Irala, Domingo Martínez de (Spanish explorer)

    Argentina: Discovery and settlement: …under Juan de Ayolas and Domingo Martínez de Irala, lieutenants of Mendoza, pushed a thousand miles up the Plata and Paraguay rivers. Ayolas was lost on an exploring expedition, but Irala founded Asunción (now in Paraguay) among the Guaraní, a largely settled agricultural people. In 1541 the few remaining inhabitants…

  • IRAM Pico Veleta Observatory (observatory, Pico Veleta, Spain)

    radio telescope: Filled-aperture telescopes: …Institut de Radioastronomie Millimétrique (IRAM) in Grenoble, France, operates a 30-metre (100-foot) antenna at an altitude of 2,850 metres (9,350 feet) on Pico Veleta in the Spanish Sierra Nevada for observations at wavelengths as short as 1 mm (0.04 inch). Several radio telescopes that operate at submillimetre wavelengths are…

  • Irāmāvatāram (work by Kampan)

    Kampan: …is the epic Irāmāvatāram (Rama’s Incarnation).

  • Iran

    Iran, a mountainous, arid, and ethnically diverse country of southwestern Asia. The country maintains a rich and distinctive cultural and social continuity dating back to the Achaemenian period, which began in 550 bce. Since 1979 it has become known for its unique brand of Islamic republic.

  • Iran Air flight 655 (aviation disaster, over the Strait of Hormuz, Persian Gulf [1988])

    Iran Air flight 655, flight of an Iranian airliner that was shot down by the missile cruiser USS Vincennes on July 3, 1988, over the Strait of Hormuz, killing all 290 people on board. The passenger plane, which was in Iranian airspace, had been incorrectly identified as a fighter jet. • U.S.-Iran

  • Iran and Libya Sanctions Act (United States [1996])

    Iran: Overview: The Iran and Libya Sanctions Act of 1996 expanded an existing U.S. embargo on the import of Iranian petroleum products to encompass extensive bans on investment both by U.S. and non-U.S. companies in Iran. These prohibitions included bans on foreign speculation in Iranian petroleum development, the…

  • Iran hostage crisis (United States history)

    Iran hostage crisis, international crisis (1979–81) in which militants in Iran seized 66 American citizens at the U.S. embassy in Tehrān and held 52 of them hostage for more than a year. The crisis, which took place during the chaotic aftermath of Iran’s Islamic revolution (1978–79) and its

  • Iran in 2006: A Country at a Crossroads

    One spring afternoon in 1997, the telephone at the New York Times bureau in Istanbul rang. I was then serving as bureau chief, and the caller was my boss, the Times foreign editor. An election was soon to be held in Iran, he said, and he had chosen me to cover it. “Get yourself a visa,” he told me,

  • Iran Mountains (mountains, Indonesia)

    Baram River: Rising in the Iran Mountains, it flows 250 miles (400 km) west and northwest, mostly through primary rain forest to the South China Sea at Baram Point. Above the lowest 100 miles, gorges and rapids make upstream navigation difficult. The Baram is Sarawak’s second longest river; its tributaries…

  • Iran nuclear deal (international agreement)

    Joint Comprehensive Plan of Action (JCPOA), more commonly known as “the Iran nuclear deal,” is a 2015 agreement between Iran and several world powers to restrict Iran’s nuclear program in exchange for relief of international sanctions on Iran. The deal was negotiated by the Democratic

  • Iran nuclear deal negotiations

    In his second term in office U.S. Pres. Donald Trump made it one of his first foreign policy priorities to finalize a deal with Iran, limiting its nuclear program and the reach of its military (including through ballistic missiles and support for the country’s allies in the Axis of Resistance). The

  • Iran’s presidential election of 2024

    Masoud Pezeshkian emerged as the surprise victor of an early presidential election in Iran, which was held in June–July 2024 after Ebrahim Raisi, a hard-line conservative, died unexpectedly in a helicopter crash on May 19. Raisi, one of the few figures trusted by both the security establishment and

  • Iran, ancient

    ancient Iran, historic region of southwestern Asia that is only roughly coterminous with modern Iran. The term Persia was used for centuries, chiefly in the West, to designate those regions where Persian language and culture predominated, but it more correctly refers to a region of southern Iran

  • Iran, flag of

    Iran’s Lion and Sun emblem was displayed on a flag as early as the 15th century, and in the late 19th century the colors green and red were added as a border to a white flag bearing those symbols. After the granting of the constitution of 1906, a tricolor typical of the national flags of many other

  • Iran, history of

    Iran: History of Iran: This article discusses the history of Iran from 640 ce to the present. For the history of the region before the 7th century, see ancient Iran.

  • Iran-Contra Affair (United States history)

    Iran-Contra Affair, 1980s U.S. political scandal in which the National Security Council (NSC) became involved in secret weapons transactions and other activities that either were prohibited by the U.S. Congress or violated the stated public policy of the government. The scandal related to U.S.

  • Iran-Iraq War (1980–1988)

    Iran-Iraq War, (1980–88), prolonged military conflict between Iran and Iraq during the 1980s. The incredibly deadly and destructive nature of the conflict left a long legacy, including the proliferation in the development of weapons of mass destruction in Iraq and Iran. The war placed tremendous

  • Irani, Ray R. (American businessman)

    Occidental Petroleum Corporation: Following Hammer’s death in 1990, Ray R. Irani became president and chief executive officer. During his 20-year tenure, Irani reduced the company’s debt burden and refocused its operations on profitable oil and gas production. Occidental’s interests in meatpacking, agricultural products, coal mining, the North Sea, and gas pipelines acquired from…

  • Iranian alphabet

    Pahlavi alphabet, writing system of the Persian people that dates from as early as the 2nd century bce, some scholars believe, and was in use until the advent of Islam (7th century ce). The Zoroastrian sacred book, the Avesta, is written in a variant of Pahlavi called Avestan. The Pahlavi alphabet

  • Iranian architecture

    ancient Iran: Art: …in an eclectic art and architecture that in itself mirrored the empire and the Persians’ understanding of how that empire ought to function. Yet the whole was entirely Persian. Just as the Achaemenids were tolerant in matters of local government and custom as long as Persians controlled the general policy…

  • Iranian highlands (mountains, Asia)

    Asia: West Asia: The Iranian highlands comprise mountain arcs (the Elburz, the Kopet-Dag, the mountains of Khorāsān, the Safīd Range, and the western Hindu Kush in the north; the Zagros, Makrān, Soleymān, and Kīrthar mountains in the south), together with the plateaus of the interior and the central Iranian,…

  • Iranian intermezzo (Iranian history)

    Iran: The Iranian intermezzo (821–1055): Yaʿqūb ibn Layth’s movement differed from Ṭāhir ibn al-Ḥusayn’s establishment of a dynasty of Iranian governors over Khorasan in 821. The latter’s rise marks the caliph’s recognition, after the difficulties encountered in Iran by Hārūn al-Rashīd (reigned 786–809), that the best way…

  • Iranian languages

    Iranian languages, subgroup of the Indo-Iranian branch of the Indo-European language family. Iranian languages are spoken in Iran, Afghanistan, Tajikistan, and parts of Iraq, Turkey, Pakistan, and scattered areas of the Caucasus Mountains. Linguists typically approach the Iranian languages in

  • Iranian literature

    Iranian literature, body of writings in the Iranian languages produced in an area encompassing eastern Anatolia, Iran, and parts of western Central Asia as well as Afghanistan and the western areas of Pakistan. The oldest surviving texts are contained in the Avesta, the sacred book of

  • Iranian low (meteorology)

    Asia: The polar front: Known as the South Asian (or Iranian) low, it appears in April and is fully developed from June to August. The onset of monsoon in India and mainland Southeast Asia is related to changes in the circulation pattern that occur by June—specifically, the disintegration of the southern jet…

  • Iranian plateau (plateau, Iran)

    Iran: Climate: …to the interior of the Iranian plateau, and low-pressure systems develop over the warm waters of the Caspian Sea, the Persian Gulf, and the Mediterranean Sea. In summer one of the world’s lowest-pressure centers prevails in the south. Low-pressure systems in Pakistan generate two regular wind patterns: the shamāl, which…

  • Iranian religion, ancient

    ancient Iranian religion, diverse beliefs and practices of the culturally and linguistically related group of ancient peoples who inhabited the Iranian plateau and its borderlands, as well as areas of Central Asia from the Black Sea to Khotan (modern Hotan, China). The northern Iranians (referred

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    Iranian Revolution, popular uprising in Iran in 1978–79 that resulted in the toppling of the monarchy on February 11, 1979, and led to the establishment of an Islamic republic. It involved the participation of a wide range of Iranians—from the secular left to the religious right—who sought an end

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    Maranao, largest of the Muslim cultural-linguistic groups of the Philippines. Numbering more than 840,000 in the late 20th century, they live around Lake Lanao on the southern island of Mindanao. Rice farming is their main livelihood, along with metalworking and woodworking handicrafts. Like the

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    Irapuato, city, west-central Guanajuato estado (state), north-central Mexico. Situated in the fertile Bajío, a valley of the central plateau, the city lies along the Irapuato River, a tributary of the Lerma River, at 5,656 feet (1,724 metres) above sea level. It is south-southwest of Guanajuato

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    Iraq, country of southwestern Asia. During ancient times, lands that now constitute Iraq were known as Mesopotamia (“Land Between the Rivers”), a region whose extensive alluvial plains gave rise to some of the world’s earliest civilizations, including those of Sumer, Akkad, Babylon, and Assyria.