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mesomorph ... mestizo
mesomorph
a human physical type (somatotype) that is marked by greater than average muscular development, as determined by the physique-classification system developed by American psychologist W.H. Sheldon. Although the Sheldon system of classification does not make absolute distinctions between types, a person is classed as a mesomorph if mesomorphy predominates over ...
meson
any member of a family of subatomic particles composed of a quark and an antiquark. Mesons are sensitive to the strong force, the fundamental interaction that binds the components of the nucleus by governing the behaviour of their constituent quarks. Predicted theoretically in 1935 by the Japanese physicist Yukawa Hideki, ...
mesonephros
permanent kidney of amphibians and most fish, developing posterior to and replacing the pronephros of the embryonic and larval stages. It is a paired organ consisting of a set of nephrons having capsules that filter blood from the glomerulus and tubules whose cells reabsorb water and nutrients and secrete nitrogenous ...
Mesopotamia
narrow, northeast-to-southwest-oriented geographic region of northeastern Argentina, comprising Misiones, Corrientes, and Entre Rios provincias (provinces), bounded on the west by the Gran Chaco of Argentina, on the north by Paraguay, on the northeast by Brazil, and on the southeast by Uruguay. Its name, meaning "between the rivers" in Greek, is ...
Mesopotamia, history of
history of the region in southwestern Asia where the world's earliest civilization developed. The name comes from a Greek word meaning "between rivers," referring to the land between the Tigris and Euphrates rivers, but the region can be broadly defined to include the area that is now eastern Syria, southeastern ...
Mesopotamian art and architecture
the art and architecture of the ancient Mesopotamian civilizations.
Mesopotamian mythology
the myths, epics, hymns, lamentations, penitential psalms, incantations, wisdom literature, and handbooks dealing with rituals and omens of ancient Mesopotamia.
Mesopotamian religion
beliefs and practices of the Sumerians and Akkadians, and their successors, the Babylonians and Assyrians, who inhabited ancient Mesopotamia (now in Iraq) in the millennia before the Christian era. These religious beliefs and practices form a single stream of tradition. Sumerian in origin, Mesopotamian religion was added to and subtly ...
mesopredator release
in ecology, a phenomenon in which populations of medium-sized predators rapidly increase in ecosystems after the removal of larger, top carnivores. Such rapid increases in mesopredator populations can force sudden changes in the structure of ecosystems as these animals assume new roles and greater influence.
Mesosaurus
early aquatic relative of reptiles, found as fossils from the Early Permian Period (299 million to 271 million years ago) in South Africa and South America.
mesoscaphe
diving vessel built by the Swiss scientist Jacques Piccard that suspended itself automatically at predetermined depths. The first mesoscaphe was built for the 1964 Swiss National Exhibition in Lausanne and designed as a tourist submarine for 40 passengers. Although it could descend to more than 600 m (2,000 feet), most ...
mesosphere
region of the upper atmosphere between about 50 and 80 km (30 and 50 miles) above the surface of the Earth. The base of the mesosphere is defined as the temperature maximum existing at the top of the stratosphere, with the boundary between the two regions usually called the stratopause. ...
mesothelioma
a tumour that arises from the sheet of cells known as the mesothelium, which lines body cavities and forms the tissue layers referred to as the pleura and the peritoneum. The pleura is located in the chest cavity, either lining the chest wall (parietal pleura) or covering the lung (visceral ...
mesozoan
any of approximately 50 species of small, ciliated, multicellular animals that parasitize other marine invertebrates belonging to the phyla Rhombozoa and Orthonectida. These wormlike organisms lack digestive, respiratory, nervous, and excretory systems; their bodies consist of two layers of as few as 20 to 30 cells each. Both sexual and ...
Mesozoic Era
second of the Earth's three major geologic eras of Phanerozoic time. Its name is derived from the Greek term for "middle life." The Mesozoic Era began 251 million years ago, following the Paleozoic Era, and ended 65.5 million years ago, at the dawn of the Cenozoic Era. The major divisions ...
Mesquite
city, Dallas county, northeastern Texas, U.S., adjacent to the city of Dallas (west). It was established in 1873 when the Texas and Pacific Railway acquired land for the town site (named for the mesquite shrubs that once covered the area), built a depot, and offered lots for sale. Until the ...
mesquite
any of the spiny, deep-rooted shrubs or small trees constituting the genus Prosopis of the pea family (Fabaceae). They form extensive thickets in areas from South America into the southwestern United States. Two races occur, one low-called running mesquite-and the other often growing into trees 15 m (50 feet) tall. ...
Mesrop Mashtots, Saint
monk, theologian, and linguist who, according to tradition, invented the Armenian script in 405 and helped establish Armenia's golden age of Christian literature.
Messager, Andre
French conductor and composer whose operettas achieved popularity in France and England.
Messali Hadj, Ahmed
revolutionary Algerian nationalist leader.
Messalina Valeria
third wife of the Roman emperor Claudius, notorious for licentious behaviour and instigating murderous court intrigues. The great-granddaughter of Augustus's sister, Octavia, on both her father's and mother's sides, she was married to Claudius before he became emperor (39 or 40). They had two children, Octavia (later Nero's wife) and ...
Messalla Corvinus, Marcus Valerius
Roman aristocrat, public servant, orator, and patron of literature.
Messapic alphabet
one of two Italian offshoots of the Tarentine-Ionic variety of the Greek alphabet. It was adopted c. 500 BC by the Messapii, who inhabited southeastern Italy in pre-Roman times.
Messapic language
Indo-European language spoken by tribes (Messapii and Iapyges) living in the southeastern part of Italy in pre-Roman and early Roman times. Messapic inscriptions date from the 6th to the 1st century BC. The language is believed to be related to the extinct Illyrian languages that were spoken on the east ...
Messapii
ancient pre-Roman people of the southeastern part of the Italian peninsula (Calabria and Apulia) who, with the closely related Iapyges, probably penetrated Italy from the other side of the Adriatic Sea about 1000 BC. They spoke an Indo-European language, Messapic. They frequently fought the Greeks of the nearby Spartan colony ...
Messene
ancient city, southwestern Peloponnese (Modern Greek: Peloponnisos), Greece, not to be confused with the modern township of the same name farther south. It was probably founded in 369 BCE after the defeat of Sparta by Athens and the Boeotian League in the Battle of Leuctra (371) for the descendants of ...
Messenger
(foaled 1780), racehorse who, though a Thoroughbred who sired many successful Thoroughbred (flat) racers, was most important as the foundation sire of the Standardbred (harness racehorse) breed. A son of Mambrino and grandson of Matchem, he was foaled in England but was taken to Philadelphia in 1788. His descendants became ...
Messenger
U.S. spacecraft that studied Mercury's surface and environment. The name was selected in honour of ancient Greek observers who perceived Mercury in its 88-day orbit of the Sun and named it for the messenger of the gods (Hermes, known to the Romans as Mercury).
messenger RNA
molecule in cells that carries codes from the DNA in the nucleus to the sites of protein synthesis in the cytoplasm (the ribosomes). In addition to mRNA, there are two other major types of RNA: ribosomal RNA (rRNA) and transfer RNA (tRNA).
Messenia
ancient district and modern nomos (department) of the southwestern Peloponnese (Modern Greek: Peloponnisos), Greece, bounded on the east by the Taiyetos (Taygetos) Mountains, on the north by the Nedha Potamos (river) and the Arcadian mountains, and on the south and west by the Ionian Sea (Iovio Pelagos). Kalamata, at the ...
Messenia, Gulf of
gulf of the Ionian Sea (Modern Greek: Iovio Pelagos) in the nomos (department) of Messenia (Messinia), southwestern Peloponnese (Peloponnisos), Greece. It is enclosed by the Likodimon Oros (mountain) and Akra (cape) Akritas on the west and the Mani peninsula on the east.
Messenian Wars
(8th-7th century BC), contests between Sparta and Messenia in ancient Greece. Many modern historians believe that there were two early Messenian wars: the first (c. 735-c. 715) was the Spartan conquest of Messenia; the second (c. 660) was precipitated by a Messenian revolt over which the Spartans were ultimately successful. ...
Messerschmitt, Willy
German aircraft engineer and designer.
Messi, Lionel
Argentine-born football (soccer) player who was named Federation Internationale de Football Association (FIFA) world player of the year in 2009, 2010, 2011, and 2012.
Messiaen, Olivier
influential French composer, organist, and teacher noted for his use of mystical and religious themes. As a composer he developed a highly personal style noted for its rhythmic complexity, rich tonal colour, and unique harmonic language.
messiah
(from Hebrew mashiah, "anointed"), in Judaism, the expected king of the Davidic line who would deliver Israel from foreign bondage and restore the glories of its golden age. The Greek New Testament's translation of the term, christos, became the accepted Christian designation and title of Jesus of Nazareth, indicative of ...
Messier catalog
(M), in astronomy, list of 110 star clusters, nebulae, and galaxies compiled by Charles Messier, who discovered many of them. The catalog is still a valuable guide to amateur astronomers, although it has been superceded by the New General Catalogue (NGC); both NGC numbers and Messier numbers remain in common ...
Messier, Charles
French astronomer who was the first to compile a systematic catalog of nebulae and star clusters. In Messier's time a nebula was a term used to denote any blurry celestial light source.
Messier, Jean-Marie
French businessman who transformed a domestic French utility company into the global media and communications conglomerate Vivendi Universal in the late 20th century.
Messikomer, Jakob
Swiss farmer and archaeologist who excavated one of the most important Late Stone Age lake dwelling sites at Robenhausen, near Lake Pfaffikon, in Switzerland.
Messina
city and port, extreme northeastern Sicily, Italy, on the lower slopes of the Peloritani Mountains, on the Strait of Messina opposite Reggio di Calabria. It was an ancient Siculan colony, first mentioned about 730 BC, founded by settlers from Chalcis, who called it Zankle ("Sickle"), from the shape of the ...
Messina earthquake and tsunami of 1908
earthquake and subsequent tsunami that devastated southern Italy on Dec. 28, 1908. The double catastrophe almost completely destroyed Messina, Reggio di Calabria, and dozens of nearby coastal towns.
Messina, Strait of
channel in the Mediterranean Sea separating Sicily (west) and Italy (east) and linking the Tyrrhenian and Ionian seas. The strait is 20 miles (32 km) long, 2 miles (3 km) wide in the north (between Faro Point and the Rock of Scylla), and 10 miles (16 km) wide in the ...
Messinian Stage
uppermost division of Miocene rocks, representing all rocks deposited worldwide during the Messinian Age (7.2 million to 5.3 million years ago) of the Neogene Period (23 million to 2.6 million years ago). The Messinian Stage is named for marine strata near Messina, Sicily.
Messmer, Otto
American animator who created the character Felix the Cat, the world's most popular cartoon star before Mickey Mouse.
Messner, Reinhold
mountain climber and polar trekker who was renowned for his pioneering and difficult ascents of the world's highest peaks. In 1978 he and Austrian Peter Habeler were the first to climb Mount Everest (29,035 feet [8,850 metres]; see Researcher's Note: Height of Mount Everest), the highest mountain in the world, ...
Mesta
society composed of all the sheep raisers of Castile, in Spain, formally recognized by Alfonso X (the Wise) in 1273. The name is thought to derive either from the Spanish mezcla ("mixture"), a reference to the mixture of sheep; or from the Arabic mechta, meaning winter pastures for sheep.
Mesta, Perle
American socialite and diplomat who entertained the world's business and political elite from the 1930s through the '50s and who also served as the first U.S. minister to Luxembourg.
mester de clerecia
poetic mode in Castilian literature of the mid-13th to 14th centuries known for its scholarship and written form, in contrast to the popular and oral mode called mester de juglaria. The mester de clerecia owes its name to its principal creators, the clergy (a term that in the Middle Ages ...
mester de juglaria
popular poetic mode in Castilian literature that was developed by Castilian minstrels between the 11th and the 14th century. It was instrumental in the creation of numerous lengthy epic poems such as Cantar de mio Cid ("The Song of the Cid") and shorter works of a narrative or lyrical nature ...
mestizo
any person of mixed blood. In Central and South America it denotes a person of combined Indian and European extraction. In some countries-e.g., Ecuador-it has acquired social and cultural connotations; a pure-blooded Indian who has adopted European dress and customs is called a mestizo (or cholo). In Mexico the description ...