Trans-Siberian Railroad, railroad in Russia, the longest in the world, stretching 5,787 mi (9,313 km) from Moscow to Vladivostock on the Sea of Japan.
21st Century Webster's Family Encyclopedia - Transcendentalism to United Church of Christ
Transcendentalism, philosophical and literary movement that flourished in New England c. 1835–60.
Transcontinental treaty See: Adams-Onís Treaty.
Transducer, device for converting an input of energy or information of one form into an output of another.
Transformer, device for moving an alternating current by increasing or decreasing the voltage.
Transfusion, blood See: Blood transfusion.
Transistor, device in electronic equipment thast regulates the flow of electricity in such equipment.
Transkei, former independent homeland established by South Africa for the black Xhosa-speaking people.
Transmigration of the soul See: Reincarnation.
Transmission, automobile part that transmits the power generated by the engine to a driving axle.
Transmutation of elements, conversion of an atom of one element to an atom of another. Since atoms are identified by their atomic number (number of protons), any change in the number of protons will result in a different element. Atoms may change their number of protons by giving off or taking in atomic particles. Transmutation occurs naturally as a result of radioactive decay. Radioactive atoms a…
Transpiration, loss of water by evaporation from the aerial parts of plants.
Transplant, organ removed from one person and surgically implanted in another to replace a lost or diseased organ. Autotransplantation is the moving of an organ from one place to another within a person, where the original site has been affected by local disease (e.g., skin grafting). Blood transfusions between those with compatible blood groups was the first practical form of transplant. In organ…
Transportation, Department of, executive department of the U.S. government responsible for the development and coordination of national transport policies and agencies.
Transsexualism, condition in which a person has a psychological urge to belong to the opposite sex.
Transuranium elements, elements of atomic number above 92.
Transvaal, former province in the Republic of South Africa, between the Vaal and Limpopo rivers in the northeast.
Transylvania, province in central Romania near the Hungarian border, situated between the Transylvanian Alps and the Carpathian Mts.
Trappists, members of the clan of the Reformed, or Strict, Observance, a Roman Catholic monastic order founded (1664) by Armand de Rancé, abbot of La Trappe in Normandy, France.
Travertine, type of limestone that forms in dense layers.
Treason, behavior by a subject or citizen that could harm the sovereign or state.
Treasury, Department of the, executive department of the U.S. government, established in 1789, responsible for federal taxes, customs, and expenditure.
Treaty, agreement between states.
Treaty of 1783 See: Revolutionary War in America.
Tree, woody perennial plant with a well-defined main stem, or trunk, that either dominates the form throughout the life cycle (giving a pyramidal shape) or is dominant only in the early stages, later forking to form a number of equally important branches (giving a rounded or flattened form to the tree). The trunk of a tree consists almost wholly of thick-walled water-conducting cells (xylem) that …
Tree frog, or tree toad, one of several hundred types of frogs belonging to the family Hylidae, commonly found in North and South America.
Tree shrew, small, squirrel-like arboreal insectivore (family Tupaiidae) with a pointed snout.
Tree toad See: Tree frog.
Trench mouth, or Vincent's infection, disease of the mouth and throat, probably caused by bacteria, poor oral hygiene, and malnutrition.
Trent Affair, naval incident in the U.S.
Trent, Council of, series of 3 conferences held in Trent, Italy, by leaders of the Roman Catholic church in the mid-16th century. Convened by Pope Paul III in 1545 to counteract the Protestant Reformation in Europe, the council did much to define Catholic doctrine and bring about a Counter-Reformation. The first council, which lasted until 1547, established the Catholic church's sole right …
Trenton (pop. 92,124), capital (since 1790) of New Jersey, situated at the head of navigation on the Delaware River, opposite Pennsylvania.
Trenton, Battle of, American victory in the Revolutionary War, fought on Dec. 26, 1776.
Trephining, surgical removal of a small, circular piece of skull.
Trevelyan, George Macauley (1876–1962), English historian who rejected the “scientific” approach to history in favor of a more humanistic and literary approach.
Triage (French, “sorting”), allocation of limited medical or food resources by selecting those in need who would most benefit in the long run.
Trial, method of settling disagreements of determining criminal guilt.
Trial by combat, medieval method of settling disagreements.
Triangle, three-sided polygon.
Trianon, Treaty of, World War I treaty that reduced Hungary's territory by almost two-thirds as punishment for its part in the war.
Triassic Period, first period of the Mesozoic Era (c.225–190 million years ago).
Tribe, people who live in a community in a particular area, sharing the same language, culture, and often kinship.
Trichina, parasitic roundworm, belonging to the trichina family, that causes an infection known as trichinosis.
Trichinosis See: Trichina.
Trier (pop. 93,500), city in southwestern Germany, on the Moselle River.
Trieste (pop. 228,400), city-seaport in northeastern Italy at the head of the Adriatic Sea, with steel, oil, and shipbuilding industries.
Triggerfish, fish belonging to the Balistidae family, found in tropical coastal waters.
Trigonometry, branch of geometry that deals with the ratios of the sides and angles of triangles, particularly of right-angled triangles and the applications of these ratios. Plane trigonometry deals with these relationships mapped on a plane surface. The principle ratios, when considering angle A of right-triangle ABC whose sides opposite the angles A, B, and C respectively are a, b, and c, and w…
Trillium, colorful wildflower (genus Trillium) of North American woodlands and eastern Asia.
Trilobite, extinct marine animal (phylum Arthropoda) from the Paleozoic Era (570–240 million years ago).
Trinidad and Tobago, officially Republic of Trinidad and Tobago, independent republic in the West Indies, consisting of 2 separate islands in the Caribbean Sea north of Venezuela. The island of Trinidad is 1,864 sq mi (4,828 sq km) and Tobago is 116 sq mi (300 sq km). The capital is Port of Spain, on Trinidad. Trinidad is very fertile and mainly flat, rising to c.3,000 ft (914 m) above sea level i…
Trinitrotoluene See: TNT.
Trinity, central doctrine of Christian theology, that there is one God who exists in three Persons and one Substance. The definition of the doctrine, implicit in the New Testament, by the early ecumenical councils (notably Nicaea and Constantinople) was the product of violent controversy with heresies like Arianism, Monophysitism, Nestorianism, and Monarchianism.It is classically summed up in the …
Triple Alliance, defense arrangement between Austria-Hungary, Germany, and Italy in the late 19th and early 20th centuries.
Triple Entente, defense pact originally formed between France and Russia in 1890 to counterbalance the threat posed by the Triple Alliance—Germany, Austria-Hungary, and Italy—8 years earlier.
Tripoli (pop. 500,000), city located in northwestern Lebanon, second largest in the country.
Tripoli (pop. 990,700), capital and largest city of Libya, located in northwest Libya on an arm of the Mediterranean Sea.
Triticale (genus Triticosecale), hybrid grain produced by crossbreeding wheat with rye.
Tritium, hydrogen isotope that is 3 times heavier than ordinary hydrogen.
Triton, in Greek mythology, sea god with human head and chest and a fishlike tail.
Triumph, Arch of See: Arc de Triomphe.
Trogon, bird of the family Trogonidae.
Trojan horse See: Trojan War.
Trojan War, conflict between Greece and Troy, made famous by Homer's Iliad.
Trollope, Anthony (1815–82), English author.
Trombone, musical instrument, one of the brass wind instruments.
Trona, carbonate mineral found in dry regions of the world or extracted from evaporated brine.
Tropic bird, graceful seabird (genus Phaethon) with long, trailing tail feathers.
Tropic of Cancer, imaginary line of latitude showing the northernmost point on the earth at which the sun can appear directly overhead.
Tropic of Capricorn, imaginary line of latitude showing the southernmost point on the earth at which the sun can appear directly overhead.
Tropical fish, any of a variety of marine and freshwater fish native to the tropics, but particularly those valued for use in aquariums because they are ornamental, small, and able to reproduce quickly and easily.
Tropical rain forest, regions of the world near the equator characterized by high levels of rainfall and humidity.
Tropics, land and water 1,600 mi (2,570 km) north and south of the equator, as defined by the Tropic of Cancer (23°27' north latitude) and the Tropic of Capricorn (23°27' south latitude).
Tropism, movement of a plant in response to external directional stimuli.
Troposphere, lowermost zone of the earth's atmosphere, extending from the earth's surface up to 5–6 mi (8–9 km) over the poles and 8–10 mi (12.8–16 km) over the equator.
Trotsky, Leon (Lev Davidovic Bronstein; 1879–1940), Russian revolutionary Communist, a founder of the USSR. President of the Petrograd (Leningrad) soviet in the abortive 1905 revolution, he escaped from prison to France, Spain, and New York. In 1917 he returned, went over to Bolshevism, and led the Bolshevik seizure of power in the October Russian Revolution. As commissar of foreign affairs…
Troubadour, name for courtly poet-musicians of Provence, southern France (1100–1300).
Trout, any of several relatives of the salmon, native to the Northern Hemisphere.
Trout lily See: Dogtooth violet.
Troy, city of ancient northwestern Asia Minor, near the Dardanelles, described in Homer's Iliad and rediscovered by Heinrich Schliemann in 1870.
Trucial states See: United Arab Emirates.
Trudeau, Edward Livingston (1848–1915), innovator of tuberculosis treatment in the United States.
Trudeau, Pierre Elliott (1919– ), Canadian prime minister (1968–79, 1980–84).
Truffaut, François (1932–84), French film director and critic.
Truffle, underground fungus (genus Tuber) that has long been regarded as a delicacy.
Trujillo Molina, Rafael Leonidas (1891–1961), Dominican Republic dictator (1930–61) and president (1930–38, 1942–52).
Truk Islands, group of islands in the western Pacific, part of the Caroline Islands.
Truman Doctrine, U.S. declaration (1947) stating the United States would “support free peoples who are resisting attempted subjugation by armed minorities or by outside pressures.” Aimed at halting communist expansion and aggression, the Truman Doctrine provided substantial aid to Greece and Turkey, helping those nations defeat communist guerrillas.
Truman, Harry S. (1884–1972), 33rd president of the United States. The challenges of Truman's presidency, which began after the sudden death of Franklin D. Roosevelt, included the end of World War II, use of the first atom bomb, the Cold War, the Marshall Plan and NATO, the controversial McCarthy hearings, and the Korean War. Truman's poor eyesight kept him out of West Point, …
Trumbull, John (1756–1843), U.S. painter.
Trumbull, Jonathan (1710–85), governor of Connecticut (1769–84).
Trumbull, Lyman (1813–96), U.S. senator from Illinois who supported antislavery legislation.
Trumpet, musical instrument, one of the brass wind instruments.
Trust, in law, legal relationship in which property is administered by a trustee, who has some of the powers of an owner, for the benefit of a beneficiary; the trustee is obliged to act only in the beneficiary's best interest and can derive no advantage except an agreed upon fee.
Trust territory, formerly dependent territory administered under United Nations supervision.
Truth, Sojourner (1797?–1883), U.S. abolitionist and feminist.
Truth table, systematic tabulation of all the possible input/output combinations produced by a binary circuit.
Trypanosome, microscopic unicellular parasite that infests the blood plasma of animals and humans, producing disease; it is transmitted by insects.
Tsar, or czar, English spellings of the Russian word for “emperor.” The term is used for the rulers of Russia from 1547 to 1917.
Tschaikowsky, Peter Ilich See: Tchaikovsky, Peter Ilich.
Tsetse fly, name for 20 species of muscoid flies (genus Glossina).
Tshombe, Moise Kapenda (1919–69), president (1960–63) of the Congolese breakaway state of Katanga.
Tsimshian, Native American tribe, residing in British Columbia along the Nass and Skeena rivers.
Tuamotu Islands, group of 75–80 small islands and atolls spanning nearly 1,000 mi (1,609 km) in the South Pacific Ocean.
Tuareg, Berber tribe in the Sahara.
Tuatara (Sphenodon punctatus), reptile resembling the lizard.
Tuba, low-pitched brass musical wind instrument with three to five valves.
Tuber, swollen, underground stem or root that contains stored food material; they are prennial.
Tuberculosis (TB), group of infectious diseases caused by the bacillus Mycobacterium tuberculosis, which kills some 3 million people every year throughout the world. TB may invade any organ but most commonly affects the respiratory system, where it has been called consumption or phthisis. In 1906 it killed 1 in every 500 persons in the United States, but today it leads to only 1 in 30,000 deaths b…
Tuberose (Polianthes tuberosa), tropical plant of the agave family, native to Asia and America but cultivated elsewhere for its use in perfumes and other products.
Tubman, Harriet (c.1820–1913), U.S. abolitionist.
Tubman, William Vacanarat Shadrach (1895–1971), president of Liberia (1944–71).
Tucker, Richard (1914–75), U.S. opera singer.
Tucson (pop. 415,100), city in southeast Arizona, inc. 1877.
Tudor, Antony (1909–87), English choreographer who introduced dramatic, emotional themes into U.S. ballet.
Tudor, House of, reigning dynasty of England (1485–1603).
Tuileries, former royal palace in Paris.
Tularemia, or rabbit fever, infectious disease due to bacteria (Pasteurella tularensis), causing fever, ulceration, lymph node enlargement, and sometimes pneumonia.
Tulip, name for plant (genus Tulipa) native to Europe and Asia, grown from bulbs.
Tuliptree See: Yellow poplar.
Tulsa (pop. 375,300), city in northeast Oklahoma, on the Arkansas River.
Tumbleweed, common name for several plants native to North America that grow in clumps on waste land and dry into loose balls.
Tumboa See: Welwitschia.
Tumor, or neoplasm, abnormal overgrowth of tissue.
Tuna, high-speed fish with rows of finlets on the tail.
Tundra, plains of the Arctic Circle.
Tungsten, or wolfram, chemical element, symbol W; for physical constants see Periodic Table.
Tunis (pop. 596,700), capital city of Tunisia, on the Lake of Tunis, in northeastern Tunisia.
Tunisia, republic in North Africa. With an area of some 63,362 sq mi (164,150 sq km), Tunisia is bounded on the south by Libya, on the west by Algeria, and on the north and east by the Mediterranean Sea. The Cape Bon peninsula, in the extreme northeast, is only 96 mi (153 km) from Sicily. Tunis is the capital and chief port. Tunisia's irregular coastline has several good harbors, among them…
Tunnel, underground passageway usually designed to carry a highway or railroad, to serve as a conduit for water or sewage, or to provide access to an underground working face. Although tunnels have been built since prehistoric times, tunneling methods remained primitive and hazardous until the 19th century. Modern softground tunneling was pioneered by Marc Brunel, who invented the “tunnelin…
Tunney, Gene (James Joseph Tunney; 1898–1978), U.S. world heavyweight boxing champion (1926–28).
Tunny See: Tuna.
Tupí-Guaraní, group of Native American tribes from central and eastern South America.
Tupelo, name of several trees belonging to the Nyssaceae family, found in Southeast Asia and in North America.
Tupper, Sir Charles (1821–1915), Canadian politican and one of the founders of the Dominion of Canada.
Turbine, machine for directly converting the kinetic and/or thermal energy of a flowing fluid (air, hot gas, steam, or water) into useful rotational energy. The working fluid either pushes against a set of blades mounted on the drive shaft (impulse turbines) or turns the shaft by reaction when the fluid is expelled from nozzles (or nozzle-shaped vanes) around its circumference (reaction turbines).…
Turbojet See: Jet propulsion.
Turbot (Psetta maxima), large flatfish found in the North Sea and Icelandic waters.
Turgenev, Ivan (1818–83), Russian writer whose realistic portrayals of the peasants and nobility of his country helped bring about social reforms and influenced later Russian writers.
Turin (pop. 952,700), city in northwestern Italy.
Turkestan, or Turkistan, large region in Asia covering parts of China, the former USSR, and Afghanistan.
Turkey, republic occupying Asia Minor and a small part of southeastern Europe. Lying between the Black and the Mediterranean seas, the Asian and European parts of Turkey are separated by the Straits, a waterway consisting of the Bosporus, the Sea of Marmara, and the Dardanelles. The Straits strategically link the Black Sea with the Mediterranean Sea. Covering 301,382 sq mi (780,574 sq km), Turkey …
Turkey, name of two species of large New World game birds, family Meleagrididae.
Turkish, Turkic language, official language of Turkey, also spoken by minorities in eastern Europe and southwestern Asia.
Turkmenistan (Republic of), independent country in central Asia, bordering Kazakhstan and Uzbekistan in the north, Afghanistan in the southeast, Iran in the south, and the Caspian Sea in the west. The Kara Kum desert covers about 90% of the landmass in this region. The country has a desert climate with hot summers and cold winters. Most of the population are Muslims, who speak a Turkic lang…
Turks, family to Turkic-speaking, chiefly Muslim people extending from Sinkiang (west China) and Siberia to Turkey, Iran, and former East European USSR.
Turks and Caicos Islands, two British colonial island groups in the West Indies.
Turner, Frederick Jackson (1861–1932), U.S. historian.
Turner, J(oseph) M(allard) W(illiam) (1775–1851), English Romantic landscape painter.
Turner, John Napier (1929– ), prime minister of Canada following the resignation of Prime Minister Pierre Trudeau.
Turner, Nat (1800–31), U.S. slave and revolutionary.
Turnip, plant (genus Brassica) native to Europe and Asia.
Turnstone, one of two types of shore birds belonging to the sandpiper family.
Turquoise, AL2(OH)3PO4H2O+Cu, igneous (volcanic) mineral containing aluminum, copper, and phosphorus, found in arid regions of the earth, especially Iran, the Sinai Peninsula, and the North American Southwest.
Turtle, reptile (order Chelonia) with a shell that almost encloses the body. A land turtle is sometimes called a tortoise, and some freshwater turtles are given the name terrapin. The turtle has existed for more than 175 million years, and there are now about 230 species spread over the warmer parts of the world, 44 of them in the United States. Some species are becoming rare because they are hunt…
Turtledove, woodland bird belonging to the pigeon and dove family.
Tuscany, region in west-central Italy, extending from the Apennine Mountains to the west coast.
Tuscarora, North American Native American tribe.
Tussock moth, type of moth belonging to the Lymantriidae family.
Tutankhamen (fl.c. 1350 B.C.), Egyptian pharaoh.
Tutu, Desmond (1931– ), South African black minister, recipient of the 1984 Nobel Peace Prize.
Tutuila See: American Samoa.
Tuva, republic of the Russian Federation between Siberia and Mongolia.
Tuvalu (formerly Ellice Islands), independent Commonwealth nation composed of nine small atolls spread over more than 500,000 sq mi (1,295,000 sq km) in the West Pacific. The capital is Fongafale on Funafuti. The largest island, Vaitupu, covers only 2 sq mi (5.2 sq km). No spot on these coral atolls rises more than 16 ft (4.9 m) above sea level. The soil is poor and there are no rivers and little …
TV See: Television.
TVA See: Tennessee Valley Authority.
Twain, Mark (Samuel Langhorne Clemens; 1835–1910), U.S. author and popular humorist and lecturer.
Tweed River, waterway forming part of the Scotland-England border.
Tweed, William Marcy ‘Boss’ (1823–78), U.S. politician.
Twelve Tables, Laws of the, earliest Roman code of laws.
Twelve-tone music, or serial music, type of music developed in the 1920s that rejects tonality as the basis for composition.
Twelve Tribes, twelve family groups into which the ancient Hebrews were divided.
Tyler, John (1790–1862), 10th president of the United States. Tyler, the first United States vice president to step into the presidency on a president's death in office, entered politics as a Democrat but was elected as a Whig. As president, however, he so opposed the Whigs' program that he was expelled from the party, burned in effigy, and threatened with impeachment. Most of…
Tyler, Moses Coit (1835–1900), critic and historian of early U.S. literature.
Tyler, Wat (d. 1381), leader of the English Peasant's Revolt (1381), England's first popular rebellion.
Tylor, Sir Edward Burnett (1832–1917), British anthropologist.
Tyndale, William (c. 1494–1536), English biblical translator.
Type, characters, including letters, numbers, and punctuation marks, assembled to form words and sentences in the printing of books, magazines, and newspapers.
Typewriter, writing machine activated manually or electrically by means of a keyboard.
Typhoid fever, infectious disease due to Salmonella typhosa, causing fever, a characteristic rash, lymph node and spleen enlargement, gastrointestinal tract disturbance with bleeding and ulceration, and usually marked malaise or prostration.
Typhus, infectious disease caused by rickettsia and carried by lice, leading to a feverish illness with a rash.
Tyrannosaurus See: Dinosaur; Prehistoric animal.
Tyre, or Sur (pop. 23,000), town in southwest Lebanon, situated on the eastern end of the Mediterranean Sea.
Tyrol, or Tirol, state in western Austria.
Tyron, William (1729–88), English governor of North Carolina (1765–71).
Tyrrhenian Sea, part of the Mediterranean Sea bounded by the west coast of Italy and by the islands of Corsica, Sardinia, and Sicily.
Tyson, Mike (1966– ), U.S. boxer.
Tyson, Mike (1966– ), U.S. boxer.
U, 21st letter of the English alphabet, corresponding to the Semitic letter waw, meaning “hook,” represented by a tenthook symbol and probably derived from an ancient Egyptian symbol for a pole support.
U-2, U.S. spy plane used during the 1950s and 1960s.
U-235, any of the different forms of an isotope of the element uranium with a mass number of 235 (the number of protons and neutrons in the atom's nucleus).
U-238 See: Uranium.
U-boat See: Submarine.
Ubangi River, chief northern tributary of the Zaire (Congo) River, in central Africa.
Ucayali River, chief headstream of the Amazon, in northern Peru.
Uccello, Paolo (c. 1397–1475), Florentine early Renaissance painter, noted for his use of perspective.
Udall, Nicolas (1505–56), English schoolmaster, scholar, and playwright.
Uffizi Palace, 16th-century palace in Florence, Italy, built by Giorgio Vassari for Cosimo I de' Medici as a public office building.
UFO See: Unidentified flying object.
Uganda, landlocked republic in east-central Africa. Covering 93,070 sq mi (241,040 sq km), Uganda is bordered by Tanzania and Rwanda in the south, Sudan in the north, Zaire in the west, and Kenya in the east. The capital is Kampala. More than 80% of the land area of Uganda consists of a fertile plateau some 3,000 to 5,000 ft (914–1,524 m) above sea level, with highlands to the east a…
Ugarit, ancient capital city of the Ugarit Kingdom of northwestern Syria, discovered in 1929 by French archeologists.
UHF waves See: Ultrahigh frequency waves.
Ukraine (Republic of), independent country in Eastern Europe, bordered by Poland to the northwest; by Slovakia, Hungary, Romania, and Moldavia to the southwest; by the Black Sea and the Sea of Azov to the south; by Russia to the northeast and east; and by Byelorussia to the north. The capital is Kiev. Ukraine consists for a large part of lowlands, with mountains on the Crimean and in the west: the…
Ukranian, East Slavic language of the Slavonic group, closely related to Russian, from which it diverged c.1200.
Ukulele, small guitarlike instrument.
Ulan Bator (pop. 619,000), capital and largest city of Mongolia.
Ulanova, Galina (1910–98), Russian prima ballerina of the Bolshoi Theater, Moscow (1944–62).
Ulbricht, Walter (1893–1973), leader of post-World War II East Germany.
Ulcer, pathological defect in skin or mucous membrane caused by inflammation due to infection, loss of blood supply, failure of venous circulation, or cancer.
Ultima Thule, ancient Greek and Roman name for lands of the far north.
Ultrahigh frequency waves (UHF), radio waves with frequencies from 300 to 3,000 megahertz (1 megahertz equals 1 million cycles per second) and with short ranges, usually less than 50 mi (80 km).
Ultramicroscope, special microscope used for studying colloidal particles (particles in solution or suspension) too small to be seen with a regular-light microscope.
Ultrasonics, science of sound waves with frequencies above those that humans can hear (above 20,000 cycles per second).
Ultraviolet rays, invisible light lying beyond the violet end of the spectrum.
Ulysses, or Odysseus, legendary hero of ancient Greece, son and successor of King Laertes of Ithaca, and husband of Penelope.
Umbilical cord, in mammals, tubelike structure linking the developing embryo, or fetus, to the placenta through most of pregnancy.
Umbrellabird, any of several crowlike birds (genus Cephalopterus) of tropical American forests, especially C. ornatus, whose crest can be expanded into an “umbrella.” It also has a lappet of feathers hanging from the throat.
UN See: United Nations.
Un-American Activities Committee (HUAC), committee of the U.S.
Unamuno, Miguel de (1864–1936), Spanish philosopher and writer, rector of Salamanca University from 1900 to his death.
Uncas (1588?–1683), chief of the Mohegans of Connecticut, celebrated in James Fenimore Cooper's The Last of the Mohicans (1826).
Uncle Sam, popular figure developed by 19th-century cartoonists and officially adopted as a U.S. national symbol in 1961.
Unconscious, in psychology, that part of the mind the individual is unable to recall at will.
Underground, term generally used for any secret political movement that seeks to overthrow a country's existing government or military authority.
Underground Railroad, secret network that helped U.S. slaves to escape from the South to the northern states and to Canada before the Civil War.
Undset, Sigrid (1882–1949), Norwegian novelist.
Undulant fever See: Brucellosis.
Unemployment, situation in which people who are normally part of the labor force are unable to find jobs.
Unemployment insurance, type of Social Security providing income to people involuntarily unemployed.
UNESCO See: United Nations Educational, Scientific, and Cultural Organization.
Ungulate, term for any mammal with hoofs.
UNICEF See: United Nations Children's Fund.
Unicorn, mythical creature with the body of a horse and one horn on its forehead.
Unicycle, single-wheeled vehicle with pedals, a seat mounted above the wheel, and no handlebars.
Unidentified flying object (UFO), object or light reprotedly seen in the air during day or night that cannot always be explained by conventional phenomena.
Unification Church, religious organization of Korean origin that became highly visible in the United States in the late 1960s.
Uniform Code of Military Justice, body of law governing all members of the U.S. armed forces.
Uniformitarianism, doctrine in geology originally opposed to Catastrophism.
Union, Act of, British Parliamentary act of 1840 that officially united Upper Canada and Lower Canada.
Union of South Africa See: South Africa.
Union of Soviet Socialist Republics (USSR) also known as the Soviet Union. Name of a union of 15 Soviet republics that desintegrated in 1991. Now independent countries, the constituent republics were Armenia, Azerbaijan, Estonia, Georgia, Kazachstan, Kirgizstan, Latvia, Lithuania, Moldova, Russian Federation, Turkmenistan, Ukraine and Uzbekistan. The union covered more than half of Europe and two-…
Unions, labor, workers' organizations formed to improve pay, working conditions, and benefits through collective power. Modern labor unions arose out of the concentrations of workers created by the Industrial Revolution. A craft (horizontal) union organizes workers by their particular skill; an industrial (vertical) union includes all workers in an industry. Unions negotiate contracts with …
Unitarianism, unorthodox Protestant faith that rejects the Trinity and the divine nature of Christ, and asserts the unipersonality of God.
Unitas, John (1933– ), U.S. football player.
United Arab Emirates, federation of emirates in the eastern Arabian Peninsula, bordered in the north by the Persian Gulf, in the east by the Gulf of Oman, in the south by Oman, in the south and west by Saudi Arabia, and in the northwest by Qatar. It comprises Abu Dhabi, Ajman, Dubai, Fujairah, Ras al-Khaimah, Sharjah, and Umm al-Qaiwain. The city of Abu Dhabi is the capital. The indigenous populat…
United Arab Republic (UAR), union of Egypt and Syria proclaimed in 1958 as a step toward Arab unity.
United Automobile Workers (United Automobile, Aerospace and Agricultural Implement Workers of America), second-largest U.S. industrial labor union, with local affiliates in Canada.
United Church of Canada, Protestant church formed in 1925 by the union of Methodist and most Presbyterian and Congregationalist churches.
United Church of Christ, U.S.