Britannica
Encyclopedias since 1768  
ABCDEFGHIJKLMNOPQRSTUVWXYZ0-9
immersed tube ... inbreeding
immersed tube
technique of underwater tunneling used principally for underwater crossings. The method was pioneered by the American engineer W.J. Wilgus in the Detroit River in 1903 for the Michigan Central Railroad. Wilgus dredged a trench in the riverbed, floated segments of ...
immersion foot
a painful disorder of the foot involving damage to the skin, nerves, and muscle that is caused by prolonged exposure to cold dampness or by prolonged immersion in cold water. See frostbite.
Immigration Restriction Act
(1901), in Australian history, fundamental legislation of the new Commonwealth of Australia that effectively stopped all non-European immigration into the country and that contributed to the development of a racially insulated white society. Representing a widespread sentiment in all of ...
immortality
in philosophy and religion, the continuity of human spiritual existence after the death of the body. The concept of immortality is to be distinguished from that of bodily resurrection.
immune system
the complex group of defense responses found in humans and other advanced vertebrates that helps repel disease-causing organisms (pathogens). Immunity from disease is actually conferred by two cooperative defense systems, called nonspecific, innate immunity and specific, acquired immunity. Nonspecific protective ...
immune system disorder
any of various failures in the body's defense mechanisms against infectious organisms (see table). Disorders of immunity include immune deficiency diseases, such as AIDS, that arise because of a diminution of some aspect of the ...
immunity
in law, exemption or freedom from liability. In England and the United States a legislator is immune from civil liability for statements made during legislative debate. He is also immune from criminal arrest, although he is subject to legal action ...
immunization
process by which resistance to disease is acquired or induced in plants and animals. This discussion focuses on immunization against infectious diseases in vertebrate animals, specifically humans.
immunology
the scientific study of the body's resistance to invasion by other organisms (i.e., immunity). In a medical sense, immunology deals with the body's system of defense against disease-causing microorganisms and with disorders in that system's functioning. The artificial induction of ...
Imo
state, southern Nigeria. Imo is bordered by the states of Anambra to the north, Abia (until 1991 part of Imo state) to the east, and Rivers to the south and west. The British first entered the territory in 1901, when ...
Imola
town and episcopal see, Bologna provincia, Emilia-Romagna regione, northern Italy. Imola lies along the Santerno River, southeast of Bologna. Its Forum Cornelii was a station on the Roman road Via Aemilia. The town was devastated in the 6th century by ...
impact crater
any feature on the continents that has been created by the impact of cosmic bodies (meteorites, asteroids, or comets) on the Earth's surface. In fact, the collision of a Mars-sized body with the Earth early in the history of the ...
impala
(Aepyceros melampus), swift-running antelope, family Bovidae (order Artiodactyla), that is found in large herds, usually near water, on the savannas and open woodlands of central and southern Africa.
impasto
paint that is applied to a canvas or panel in quantities that make it stand out from the surface. Impasto was used frequently to mimic the broken-textured quality of highlights-i.e., the surfaces of objects that are struck by an intense ...
Impatiens
large genus of herbaceous plants, belonging to the balsam family (Balsaminaceae), that are widely distributed in Asia, Africa, and North America. Some are regarded as weeds but others are popular garden plants. The name, meaning "impatient," refers to the readiness ...
impeachment
in common law, a criminal proceeding instituted against a public official by a legislative body. In Great Britain the House of Commons serves as prosecutor and the House of Lords as judge in an impeachment proceeding. In the federal government ...
Imperia
capital of Imperia provincia, Liguria regione, northwestern Italy. It lies on that part of the Riviera di Ponente known as the Riviera dei Fiori, northeast of San Remo. Formed in 1923 by the union of Porto Maurizio, Oneglia, and several ...
Imperial Chemical Industries PLC
major British corporation that was founded in 1926 as Imperial Chemical Industries Ltd. to amalgamate four major British chemical companies: Brunner, Mond & Co. Ltd., Nobel Industries Ltd., United Alkali Company Ltd., and British Dyestuffs Corporation Ltd. Between World Wars ...
imperial city
any of the cities and towns of the Holy Roman Empire that were subject only to the authority of the emperor, or German king, on whose demesne (personal estate) the earliest of them originated. The term freie Reichsstadt, or Free ...
Imperial College of Science, Technology and Medicine
institution of higher learning in London, affiliated with the University of London. It is one of the leading research colleges or universities in England. Its main campus is located in South Kensington (in Westminster), and its medical school is linked ...
Imperial Crown
crown created in the 10th century for coronations of the Holy Roman emperors. Although made for Otto the Great (912-973), it was named for Charlemagne, the first Holy Roman emperor.
Imperial Group, PLC
leading British manufacturer of tobacco products, including Player and Embassy cigarettes, Wilson's snuff, and several brands of cigars. Its other products included beer, prepared foods, and packaging. Corporate headquarters are in London.
imperial preference
historically, a commercial arrangement in which preferential rates (i.e., rates below the general level of an established tariff) were granted to one another by constituent units of an empire. Imperial preference could also include other sorts of preference, such as ...
Imperial Valley
intensively irrigated part of the Colorado Desert, mainly in Imperial county, southern California, U.S. The valley extends southward for 50 miles (80 km) from the southern end of the Salton Sea (a saline lake) into Mexico. Part of a trough ...
Imperial War Museum
in the United Kingdom, national museum serving as a memorial and record of the wartime efforts and sacrifices of the people of Great Britain and the Commonwealth. Upon its opening in 1920, its focus was on World War I, but ...
imperialism
state policy, practice, or advocacy of extending power and dominion, especially by direct territorial acquisition or by gaining political and economic control of other areas. Because it always involves the use of power, whether military force or some subtler form, ...
imperium
(Latin: "command," "empire"), the supreme executive power in the Roman state, involving both military and judicial authority. It was exercised first by the kings of Rome; under the republic (c. 509 BC-27 BC) it was held by the chief magistrates ...
impetigo
inflammatory skin infection that begins as a superficial blister or pustule that then ruptures and gives rise to a weeping spot on which the fluid dries to form a distinct honey-coloured crust. Impetigo is caused by Staphylococcus ...
Imphal
capital of Manipur state and administrative headquarters of Manipur Central district, northeastern India, lying in the Manipur River Valley, at an altitude of 2,500 ft (760 m). Imphal was the seat of the kings of Manipur before the region fell ...
implantation
in reproduction physiology, the adherence of a fertilized egg to a surface in the reproductive tract, usually to the uterine wall (see uterus), so that the egg may have a suitable environment for growth and development into a new offspring. ...
implication
in logic, a relationship between two propositions in which the second is a logical consequence of the first. In most systems of formal logic, a broader relationship called material implication is employed, which is read "If A, then B," and ...
impotence
in general, the inability of a man to achieve or maintain penile erection and hence the inability to participate fully in sexual intercourse. In its broadest sense the term impotence refers to the inability to become sexually aroused; in this ...
Impressionism
a major movement, first in painting and later in music, that developed chiefly in France during the late 19th and early 20th centuries. Impressionist painting comprises the work produced between about 1867 and 1886 by a group of artists who ...
impressment
enforcement of military or naval service on able-bodied but unwilling men through crude and violent methods. Until the early 19th century this practice flourished in port towns throughout the world. Generally impressment could provide effective crews only when patriotism was ...
imprimatur
(Latin: "let it be printed"), in the Roman Catholic church, a permission, required by contemporary canon law and granted by a bishop, for the publication of any work on Scripture or, in general, any writing containing something of peculiar significance ...
imprinting
in psychobiology, a form of learning in which a very young animal fixes its attention on the first object with which it has visual, auditory, or tactile experience and thereafter follows that object. In nature the object is almost invariably ...
imprinting
process of transferring writing from a master copy to another form. There are three basic methods of imprinting: (1) spirit hectograph master cards, (2) stencil cards, and (3) metal or plastic plates. Hectograph master cards are made with the aid ...
impromptu
a 19th-century piano composition intended to produce the illusion of spontaneous improvisation. In keeping with this fundamental premise, there is no particular form associated with the impromptu, although ternary and rondo schemes are common. The style of the music is ...
improvisation
in theatre, the playing of dramatic scenes without written dialogue and with minimal or no predetermined dramatic activity. The method has been used for different purposes in theatrical history. The theatrical form known as the commedia dell'arte was highly improvisational, ...
improvisation
in music, the extemporaneous composition or free performance of a musical passage, usually in a manner conforming to certain stylistic norms but unfettered by the prescriptive features of a specific musical text. Music originated as improvisation and is still extensively ...
imram
in early Irish literature, a story about an adventurous voyage. This type of story includes tales of Irish saints traveling to Iceland or Greenland, as well as fabulous tales of pagan heroes journeying to the otherworld (echtrae). An outstanding example ...
Imredy, Bela
right-wing politician and premier of Hungary (1938-39), whose close collaboration with the Nazis during World War II led to his execution as a war criminal.
Imru' al-Qays
Arab poet, acknowledged as the most distinguished poet of pre-Islamic times by the Prophet Muhammad, by 'Ali, the fourth caliph, and by Arab critics of the ancient Basra school. He is author of one of the seven odes in the ...
in medias res
in narrative technique, the recommended practice of beginning an epic or other fictional form by plunging into a crucial situation that is part of a related chain of events; the situation is an extension of previous events and will be ...
In Memoriam stanza
a quatrain in iambic tetrameter with a rhyme scheme of abba. The form was named for the pattern used by Alfred, Lord Tennyson in his poem In Memoriam, which, following an 11-stanza introduction, begins I held it truth, with him ...
In nomine
style of 16th- and 17th-century English instrumental ensemble music based on the plainsong melody of the antiphon (a verse originally sung before and after a psalm in the Roman Catholic liturgy) "Gloria tibi Trinitas" ("Glory to Thee, O Trinity") from ...
in vitro fertilization
medical procedure in which mature egg cells are removed from a woman, fertilized with male sperm outside the body, and inserted into the uterus of the same or another woman for normal gestation. Although in vitro fertilization with reimplantation of ...
Inari
in Japanese mythology, god primarily known as the protector of rice cultivation. The god also furthers prosperity and is worshiped particularly by merchants and tradesmen, is the patron deity of swordsmiths and is associated with brothels and entertainers.
Inari, Lake
largest lake in Lapin laani (province), northern Finland, lying near the Russian border. At an elevation of 389 feet (119 m), it is approximately 50 miles (80 km) long and 25 miles wide at its farthest points, has an area ...
Inazawa
city, Aichi ken (prefecture), Honshu, Japan, in the Owari plain. It was a small rural town during the Tokugawa period (1603-1867), producing vegetables for the market of nearby Nagoya. Increased urbanization in the area since World War II, however, sparked ...
inbreeding
the mating of individuals or organisms that are closely related through common ancestry, as opposed to outbreeding, which is the mating of unrelated organisms. Inbreeding is useful in the retention of desirable characteristics or the elimination of undesirable ones, but ...
© 2006 Encyclopædia Britannica Australia Ltd
Encyclopedia Home | World Atlas