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  • Macrocystis (kelp)
    genus of brown algae, like Laminaria (but larger), commonly known as kelp....
  • Macrocystis pyrifera (seaweed)
    ...to rock in even a gentle ocean surge; as a result this plant is largely restricted to sheltered shores. The fastest-growing plant—adding as much as 1 metre per day to its length—is the giant kelp, Macrocystis pyrifera, which is found on subtidal rocky reefs. These plants, which may exceed 30 metres in length, characterize benthic habitats on many temperate reefs. Large......
  • macrocyte (cell)
    ...These cells, called megaloblasts, are for the most part destroyed in the bone marrow and are not released to the circulation. Some megaloblasts mature to become large red blood cells called macrocytes; they reach the circulation but function abnormally. A deficiency of white blood cells (leukopenia) and of platelets (thrombocytopenia) is also seen in the blood....
  • macrocytic anemia (pathology)
    Anemias are classified on morphological grounds. Macrocytic anemia, in which the average size of circulating red cells is larger than normal, results from impaired production of red cells—e.g., when vitamin B12 or folic acid is lacking. In other circumstances—for example, when there is a deficiency of iron—the circulating red cells are smaller than normal and poorly...
  • macrocytic hyperchromic anemia (pathology)
    Anemias are classified on morphological grounds. Macrocytic anemia, in which the average size of circulating red cells is larger than normal, results from impaired production of red cells—e.g., when vitamin B12 or folic acid is lacking. In other circumstances—for example, when there is a deficiency of iron—the circulating red cells are smaller than normal and poorly...
  • Macrodactylus subspinosus (insect)
    A well-known, destructive chafer is the rose chafer (M. subspinosus), a tan, long-legged beetle that feeds on the flowers and foliage of grapes, roses, and other plants. Poultry that eat rose chafer grubs may be poisoned. Other scarab subfamilies also include species called chafers (see also flower chafer; shining leaf chafer)....
  • Macrodasyida (gastrotrich order)
    ...or in bands on the ventral surface of the body; cuticle, often with spines, scales, or plates; muscular triradiate pharynx, but without corona or mastax.Order MacrodasyidaMarine; adhesive tubes, often numerous, along the body.Order ChaetonotidaMostly freshwater; disti...
  • Macroderma gigas (Macroderma gigas)
    some of the few bats known to possess white or gray fur; not every bat with white fur is called a ghost bat. Ghost bats are tropical, but only one, also called the Australian giant false vampire bat (Macroderma gigas), is found outside Central and South America. The four ghost bat species of the New World belong to the genus Diclidurus....
  • Macrodipteryx longipennis (bird)
    The migratory behaviour of birds has a unique regularity in Africa, where life zones are arranged symmetrically by latitudes away from the Equator. Some migrants never cross the Equator. The standard-wing nightjar (Macrodipteryx longipennis), which nests in a belt extending from Senegal in the west to Kenya in the east along the equatorial forest, migrates northward to avoid the wet......
  • Macrodyasoidea (gastrotrich order)
    ...or in bands on the ventral surface of the body; cuticle, often with spines, scales, or plates; muscular triradiate pharynx, but without corona or mastax.Order MacrodasyidaMarine; adhesive tubes, often numerous, along the body.Order ChaetonotidaMostly freshwater; disti...
  • macroeconomics
    study of national or regional economies in terms of the total amount of goods and services produced, the total income earned, the level of employment of productive resources, and the general behaviour of prices. Until the 1930s most economic analysis concentrated on individual firms and industries. Growth in the field of macroeconomics paralleled the development of the concepts ...
  • macroencephaly (pathology)
    Macroencephaly is a congenital malformation in which expansion of the brain usually results from a variety of disorders, including hydrocephalus. In Aarskog syndrome the eyes are set unusually far apart, and in craniostenosis the sutures of the skull do not develop, so that the skull grows abnormally. In hemiatrophy half of the skull and face may develop abnormally, in which case the brain also......
  • macrofauna (biology)
    in soil science, animals that are one centimetre or more long but smaller than an earthworm. Potworms, myriapods, centipedes, millipedes, slugs, snails, fly larvae, beetles, beetle larvae, and spiders are typical members of the macrofauna. Many of these animals burrow in the soil, aiding soil drainage and aeration; in addition, some organic material passes into the soil through the burrows. Most ...
  • macrogamete (plant anatomy)
    in biology, the female sex cell, or gamete. In botany the egg is sometimes called a macrogamete. In zoology the Latin term for egg, ovum, is frequently used to refer to the single cell, while the word egg may be applied to the entire specialized structure or capsule that consists of the ovum, its various protective membranes, and any accompanying nutritive materials. The human female......
  • macroglossia (pathology)
    enlargement of the tongue, due to overdevelopment of the muscle or the accumulation of material within the tongue. Muscular hypertrophy may be congenital, as in Down syndrome, or may develop later in life, as in acromegaly. Inadequate lymph drainage caused by infection, tumours, or other obstructions leads to enlargement of the tongue, as do...
  • Macroglossus
    ...found on tropical islands from Madagascar to Australia and Indonesia. They are the largest of all bats. Some of the smallest members of the family are the pollen- and nectar-eating long-tongued fruit bats (Macroglossus), which attain a head and body length of about 6–7 cm (2.4–2.8 inches) and a wingspan of about 25 cm (10 inches). Colour......
  • Macroglossus minimus (bat)
    ...found on tropical islands from Madagascar to Australia and Indonesia. They are the largest of all bats. Some of the smallest members of the family are the pollen- and nectar-eating long-tongued fruit bats (Macroglossus), which attain a head and body length of about 6–7 cm (2.4–2.8 inches) and a wingspan of about 25 cm (10 inches). Colour.........
  • macrolide (drug)
    The macrolides (e.g., erythromycin, clarithromycin, azithromycin) are usually administered orally, but they can be given parenterally. These drugs, which inhibit protein synthesis, are valuable in treating pharyngitis and pneumonia caused by Streptococcus in persons sensitive to penicillin. They are also used in treating pneumonias caused either by ......
  • Macromedia (American company)
    The macrolides (e.g., erythromycin, clarithromycin, azithromycin) are usually administered orally, but they can be given parenterally. These drugs, which inhibit protein synthesis, are valuable in treating pharyngitis and pneumonia caused by Streptococcus in persons sensitive to penicillin. They are also used in treating pneumonias caused either by .........
  • macromere (cell)
    ...four cells (blastomeres) give rise, by alternating clockwise and counterclockwise divisions, to a cap of smaller cells, called micromeres, at one end of the egg and a cap of larger cells, called macromeres, at the other end....
  • macromineral
    As nutrients, minerals are traditionally divided into two groups according to the amounts present in and needed by the body. The major minerals (macrominerals)—those required in amounts of 100 milligrams or more per day—are calcium, phosphorus (phosphates), magnesium, sulfur, sodium, chloride, and potassium. The trace......
  • macromolecular peptide (biochemistry)
    highly complex substance that is present in all living organisms. Proteins are of great nutritional value and are directly involved in the chemical processes essential for life. The importance of proteins was recognized by the chemists in the early 19th century who coined the name for these substances from the Greek proteios, meaning “holding first place.” Proteins are species-specif...
  • macromolecule (chemistry)
    any very large molecule, usually with a diameter ranging from about 100 to 10,000 angstroms (10-5 to 10-3 millimetre). The molecule is the smallest unit of the substance that retains its characteristic properties; the macromolecule is such a unit but is considerably larger than the ordinary molecule, which usually has a diameter of less than 10 angstrom...
  • Macronectes giganteus (bird)
    The giant fulmar, also known as the giant petrel (Macronectes giganteus), with a length of about 90 cm (3 feet) and a wingspread in excess of 200 cm (6.5 feet), is by far the largest member of the family. This species nests on islands around the Antarctic Circle and in sub-Antarctic waters. It feeds on live and dead animal matter of all kinds and is a heavy predator on the young of many......
  • macronucleus (biology)
    relatively large nucleus believed to influence many cell activities. It occurs in suctorian and ciliate protozoans (e.g., Paramecium). The macronucleus is associated with one or more smaller micronuclei, which are necessary for conjugation and autogamy (reproduction by exchange between the nuclei of different individuals and of the same individuals, respectively). When these reproductive p...
  • macronutrient (biology)
    ...vitamins, minerals, and water. Carbohydrates, lipids, and proteins constitute the bulk of the diet, amounting together to about 500 grams (just over one pound) per day in actual weight. These macronutrients provide raw materials for tissue building and maintenance as well as fuel to run the myriad of physiological and metabolic activities that sustain life. In contrast are the......
  • Macropædia
    ...of Britannica 3, or the 15th edition, in 1974. The new set consisted of 28 volumes in three parts serving different functions: the Micropædia (Ready Reference), Macropædia (Knowledge in Depth), and Propædia (Outline of Knowledge). The 15th edition was given a world point of view by more than 4,000 contributing authors from...
  • macrophage (cell)
    ...move through the circulation, they are engulfed by phagocytes. Phagocytic cells form a part of the lining of blood vessels, particularly in the spleen, liver, and bone marrow. These cells, called macrophages, are constituents of the reticuloendothelial system and are found in the lymph nodes, in the intestinal tract, and as free-wandering and fixed cells. As a group they have the ability to......
  • macrophage system (physiology)
    class of cells that occur in widely separated parts of the human body and that take up particular substances. These cells are part of the body’s defense mechanisms....
  • macrophotography
    Near photography to reveal fine texture and detail covers several ranges: (1) close-up photography at image scales between 0.1 and 1 (one-tenth to full natural size); (2) macrophotography between natural size and 10 to 20× magnification, using the camera lens on its own; (3) photomicrography at magnifications above about 20×, combining the camera with a microscope; and (4) electron.....
  • macrophyte (biology)
    ...Figure 4. Included are the plankton, which contains tiny floating plants (phytoplankton) and animals (zooplankton) as well as microbes (see marine ecosystem: Marine biota: Plankton); the shoreline macrophytes; the benthos (bottom-dwelling organisms); the nekton (free-swimming forms in the water column); the periphyton (microscopic biota on submerged objects); the psammon (biota buried in......
  • Macropinna microstoma (species)
    The barreleye (Macropinna microstoma), a spookfish of the Pacific, occurs along the North American coast. It is less than 10 cm (4 inches) in length and brownish in colour....
  • Macropipus (crab genus)
    The third type of superposition eye, discovered in 1988 in the crab genus Macropipus by Swedish zoologist Dan-Eric Nilsson, has optical elements that use a combination of a single lens and a parabolic mirror. The lens focuses an image near the top of the clear zone (similar to an apposition eye), but oblique rays are intercepted by a parabolic mirror surface that lines the......
  • Macropodia rostrata (crab)
    Majids, a widely distributed marine group, are fished commercially in temperate waters, such as in the North Pacific. Some are quite small; for example, the long-beaked spider crab (Macropodia rostrata) of European coastal waters has a body about 1 cm (less than 0.5 inch) in diameter. The largest spider crab, and perhaps the largest known arthropod, is the giant crab (q.v.) of the......
  • Macropodidae (marsupial)
    any of six large species of Australian marsupials noted for hopping and bouncing on their hind legs. The term kangaroo, most specifically used, refers to the eastern gray kangaroo, the western gray kangaroo, and the red kangaroo, as well as to the antilopine kangaroo and two species of wallaroo (see below). Less specifically, kangaroo refers to all 13 specie...
  • Macropus antilopinus (marsupial)
    The antilopine kangaroo (M. antilopinus), sometimes called the antilopine wallaroo, replaces the red kangaroo in the plains of the tropical north, from Cape York Peninsula in the east to the Kimberleys in the west. It is smaller than the red kangaroo and more wallaroo-like in general appearance, although it is more slenderly built. The antilopine kangaroo is an extremely fast hopper. The......
  • Macropus elegans (marsupial)
    ...wallaby (M. rufogriseus), with reddish nape and shoulders, which inhabits brushlands of southeastern Australia and Tasmania; this species is often seen in zoos. The pretty-faced wallaby, or whiptail (M. elegans, or M. parryi), with distinctive cheek marks, is found in open woods of coastal eastern Australia....
  • Macropus fuliginosus (marsupial)
    The eastern gray kangaroo (Macropus giganteus) is found mostly in the open forests of eastern Australia and Tasmania. It is replaced by the western gray kangaroo (M. fuliginosus) along the southern coast into the southwest of Western Australia. The ranges of the two species overlap in western New South Wales and western Victoria. Both species, but especially the eastern, prefer......
  • Macropus giganteus (marsupial)
    The eastern gray kangaroo (Macropus giganteus) is found mostly in the open forests of eastern Australia and Tasmania. It is replaced by the western gray kangaroo (M. fuliginosus) along the southern coast into the southwest of Western Australia. The ranges of the two species overlap in western New South Wales and western Victoria. Both species, but especially the eastern, prefer......
  • Macropus parryi (marsupial)
    ...wallaby (M. rufogriseus), with reddish nape and shoulders, which inhabits brushlands of southeastern Australia and Tasmania; this species is often seen in zoos. The pretty-faced wallaby, or whiptail (M. elegans, or M. parryi), with distinctive cheek marks, is found in open woods of coastal eastern Australia....
  • Macropus robustus (marsupial)
    either of two species of kangaroo-like mammals native to Australia and belonging to the genus Macropus. They are closely related to wallabies and kangaroos....
  • Macropus rufogriseus (marsupial)
    ...are built like the big kangaroos but differ somewhat in dentition. Their head and body length is 45 to 105 cm (18 to 41 inches), and the tail is 33 to 75 cm long. A common species is the red-necked wallaby (M. rufogriseus), with reddish nape and shoulders, which inhabits brushlands of southeastern Australia and Tasmania; this species is often seen in zoos. The pretty-faced......
  • Macropus rufus (marsupial)
    ...per hour; 34 mph [miles per hour]). Research has revealed a remarkable advantage to bipedal hopping. Although at low speeds kangaroos expend more energy than do quadrupeds of the same size, the red kangaroo (M. rufus) actually uses less energy at 10.1 km/hr than at 6.5 and less still at higher speeds. This seems to be related to the storage of elastic strain energy in its tendons and......
  • Macrorhamphosidae (fish)
    any of about 12 species of marine deepwater fishes of the family Macrorhamphosidae (order Gasterosteiformes), found in warm and temperate regions. Snipefishes are small, usually deep-bodied fishes that grow at most about 25 to 30 cm (10 to 12 inches) long and are commonly silver, pink, or red. They have long, tubular snouts and often bear a partial coating of armour plates along the back. The dors...
  • macroscale wind system (meteorology)
    ...cyclones and anticyclones that control day-to-day weather changes. Sometimes the planetary and synoptic scales are combined into a single classification termed the large-scale, or macroscale. Large-scale wind systems are distinguished by the predominance of horizontal motions over vertical motions and by the preeminent importance of the Coriolis force in influencing wind characteristics.......
  • Macroscelidea (mammal)
    any of 16 species of rat-sized African mammals named for their long, tapered, and flexible snout (proboscis). All have slim bodies, slender limbs, and very long hind legs and feet. Although they resemble shrews, they are not insectivores but constitute the mammalian order Macroscelidea....
  • Macroscelides proboscideus (mammal)
    In addition to the checkered elephant shrews, the family Macroscelididae also includes the long-eared elephant shrews (genus Elephantulus), the short-eared elephant shrew (Macroscelides proboscideus), and the four-toed elephant shrew (Petrodromus tetradactylus); these three genera are classified together in a......
  • macroscopic symptom (plant pathology)
    ...of cabbage leaves in hot weather resulting from clubroot or root knot). Microscopic disease symptoms are expressions of disease in cell structure or cell arrangement seen under a microscope. Macroscopic symptoms are expressions of disease that can be seen with the unaided eye. Specific macroscopic symptoms are classified under one of four major categories: prenecrotic, necrotic,......
  • Macrosiphum euphorbiae (insect)
    The potato aphid (Macrosiphum euphorbiae) begins as black eggs on rose plants, which hatch into pink and green young that feed on rosebuds and leaves. In early spring they migrate to potatoes, which are the summer host. One generation occurs every two to three weeks. It is the carrier of tomato and potato mosaic virus diseases that kill vines and blossoms....
  • Macrosiphum rosae (insect)
    The rose aphid (Macrosiphum rosae) is large and green with black appendages and pink markings. It is common on its only host, the cultivated rose. Natural predators are ladybird larvae and aphidlions (lacewing larvae)....
  • macrosociology (sociology)
    Only a few sociologists have developed structural theories that apply to institutions and whole societies—an approach known as macrosociology. Gerhard Lenski in Power and Privilege (1966) classified societies on the basis of their main tools of subsistence and, unlike Marx, demonstrated statistically that variations in the primary tools used in a given society......
  • macrospore (plant anatomy)
    ...gametophyte individuals that are entirely dependent upon the sporophyte plant. Gymnosperms and angiosperms form two kinds of spores: microspores, which give rise to male gametophytes, and megaspores, which produce female gametophytes....
  • Macrosteles fascifrons (insect)
    The six-spotted leafhopper (Macrosteles fascifrons) is greenish yellow with six black spots. It produces several generations per year. It infects asters and other garden plants and transmits aster yellow virus, which causes excessive branching, stunted growth, and foliage to turn yellow. ...
  • Macrotermes natalensis (insect)
    ...side faces east-west, an orientation that probably functions to help regulate temperature. Spectacular mounds are built by fungus-growing termites in Indomalaya and Africa. Mounds of some African Macrotermes species reach a height of 8 to 9 metres (26.2 to 29.5 feet) and have pinnacles, chimneys, and ridges on their outer walls. Such mounds are built of fine particles of clay glued......
  • Macrotis lagotis (marsupial)
    ...be black-barred, is the common form in eastern Australia. The three species of short-nosed bandicoots, Isoodon (incorrectly Thylacis), are found in New Guinea, Australia, and Tasmania. Rabbit-eared bandicoots, or bilbies, are species of Thylacomys (sometimes Macrotis); now endangered, they are found only in remote colonies in arid interior Australia. As the name......
  • Macrotus waterhousii (Macrotus waterhousii)
    ...be black-barred, is the common form in eastern Australia. The three species of short-nosed bandicoots, Isoodon (incorrectly Thylacis), are found in New Guinea, Australia, and Tasmania. Rabbit-eared bandicoots, or bilbies, are species of Thylacomys (sometimes Macrotis); now endangered, they are found only in remote colonies in arid interior Australia. As the name........
  • Macrouridae (fish)
    any of about 300 species of abundant deep-sea fishes of the family Macrouridae found along the ocean bottom in warm and temperate regions. The typical grenadier is a large-headed fish with a tapered body ending in a long, ratlike tail bordered above and below by the anal and second dorsal fins. The eyes are large, and the mouth is on the underside of the head. The often extended snout presumably a...
  • Macrozamia (plant genus)
    genus of about 40 species of palmlike cycads (plants of the family Zamiaceae), native to Australia and grown elsewhere as ornamental and conservatory specimens. The genus includes tuberous, fernlike plants and palmlike, columnar trees that grow as high as 18 metres (about 60 feet). The pith is a source of starch, but the seeds are poisonous to livestock. The cones of Macrozamia may grow to ...
  • Macrozamia hopei (plant)
    ...a new set of leaves. After several years these dwarf shoots develop into short, stubby outgrowths from the stem. Stems of cycads are typically short and squat, although the Australian cycad Macrozamia hopei may reach 19 metres. In the centre is a large, fleshy pith surrounded by a cylinder of xylem and phloem. There never is as much secondary vascular tissue as is found in conifers,......
  • MacStiofain, Sean (Irish militant)
    British-born Irish militant (b. Feb. 17, 1928, London, Eng.—d. May 17, 2001, Navan, County Meath, Ire.), was the first chief of staff of the Provisional Irish Republican Army after the hard-line militarist wing’s split from the Official IRA in 1969. Originally drawn to the Irish republican cause by his Belfast, N.Ire.-born mother, he joined the IRA in his 20s and later changed his na...
  • Mactan Island (island, Philippines)
    coral island, central Philippines, located in the Bohol Strait off the eastern shore of the island of Cebu. Rectangular in shape, the low-lying island has extensive mangrove swamps. It protects the harbour of Cebu City....
  • Macua language
    a Bantu language that is closely related to Lomwe and is spoken in northern Mozambique. The Bantu languages form a subgroup of the Benue-Congo branch of the Niger-Congo language family. Makua had about six million speakers in the late 20th century, and Lomwe two million....
  • macula (ear anatomy)
    ...as the otolith organs (Figure 4). Because they respond to gravitational forces, they are also called gravity receptors. Each sac has on its inner surface a single patch of sensory cells called a macula, which is about 2 millimetres (0.08 inch) in diameter and which monitors the position of the head relative to the vertical (see The physiology of balance: vestibular function: Detection of......
  • macula (anatomy)
    in anatomy, the small yellowish area of the retina near the optic disk that provides central vision. When the gaze is fixed on any object, the centre of the macula, the centre of the lens, and the object are in a straight line. In the centre of the macula is a depression, called the fovea, which contains specialized nerve cells that are exclusively of the type known as cones. Co...
  • macula lutea (anatomy)
    in anatomy, the small yellowish area of the retina near the optic disk that provides central vision. When the gaze is fixed on any object, the centre of the macula, the centre of the lens, and the object are in a straight line. In the centre of the macula is a depression, called the fovea, which contains specialized nerve cells that are exclusively of the type known as cones. Co...
  • macula sacculi (anatomy)
    ...function: Detection of linear acceleration: static equilibrium). In the utricle the macula projects from the anterior wall of that tubular sac and lies primarily in the horizontal plane. In the saccule the macula is in the vertical plane and directly overlies the bone of the inner wall of the vestibule. In shape it is elongated and resembles the letter J. Each macula consists of......
  • macula utriculi (anatomy)
    ...and which monitors the position of the head relative to the vertical (see The physiology of balance: vestibular function: Detection of linear acceleration: static equilibrium). In the utricle the macula projects from the anterior wall of that tubular sac and lies primarily in the horizontal plane. In the saccule the macula is in the vertical plane and directly overlies the bone of the inner......
  • macular degeneration (medicine)
    There is evidence that intake of the antioxidants vitamin C, vitamin E, and beta-carotene as well as the mineral zinc may slow the progression of age-related macular degeneration, a leading cause of blindness in people older than 65 years. Two carotenoids, lutein and zeaxanthin, also are being studied for their possible role in protecting against age-related vision loss. Research suggests that......
  • Maculinea arion (insect)
    ...coloration. The pigmy blue (species Brephidium exilis), the smallest blue, has a wingspan of less than 12 mm; the tailed blues (Everes) have a taillike extension on the hindwings. The European blue (Maculinea arion) spends its larval and pupal stages in an ant nest, emerging in the spring as an adult....
  • Macumba (religion)
    Afro-Brazilian religion that is characterized by a marked syncretism of traditional African religions, European culture, Brazilian Spiritualism, and Roman Catholicism. Of the several Macumba sects, the most important are Candomblé and Umbanda....
  • Macunaíma (novel by Andrade)
    ...of the past led to his appreciation of Brazil’s cultural and racial heterogeneity. Nowhere is this more apparent than in his novel Macunaíma (1928; Eng. trans. Macunaíma). The constant metamorphoses that its protagonist undergoes represent not synthesis but the juxtaposition of differences between Brazil’s three major ethnic grou...
  • macuquinas (coin)
    ...being very nearly round and containing all the lettering and required symbols; but the press or mill type coinage is frequently of very poor appearance. These coins of rude mintage are called macuquinas (cob). In the 18th century, by ordinances of Philip V, the setting up of machinery for the minting of a perfectly round coinage, with milled and corded (ropelike) edge, became mandatory....
  • Macushí (people)
    ...such as the coastal Arawak proper and those of the Greater Antilles, the Achagua, Guahibo, Palicur, and others; the Carib of the Guianas, such as the Barama River Carib, the Taulipang, and the Makushí (Macushí); the Tupians of the coast of Brazil, such as the Tupinambá; and inland groups among whom were the Mundurukú, Kawaíb (Parintintín), and......
  • Macusi (people)
    ...such as the coastal Arawak proper and those of the Greater Antilles, the Achagua, Guahibo, Palicur, and others; the Carib of the Guianas, such as the Barama River Carib, the Taulipang, and the Makushí (Macushí); the Tupians of the coast of Brazil, such as the Tupinambá; and inland groups among whom were the Mundurukú, Kawaíb (Parintintín), and......
  • Macy and Company, Inc. (American retailer)
    major American department store chain. Its principal outlet, the 11-story department store that occupies a city block at New York City’s Herald Square (34th Street and Broadway), was for many years physically the largest single store in the country. Headquarters are in New York City....
  • Macy, Anne Sullivan (American educator)
    American teacher of Helen Keller, widely recognized for her achievement in educating to a high level a person without sight, hearing, or normal speech....
  • Macy’s (American retailer)
    major American department store chain. Its principal outlet, the 11-story department store that occupies a city block at New York City’s Herald Square (34th Street and Broadway), was for many years physically the largest single store in the country. Headquarters are in New York City....
  • Macy’s, Inc. (American retailer)
    major American department store chain. Its principal outlet, the 11-story department store that occupies a city block at New York City’s Herald Square (34th Street and Broadway), was for many years physically the largest single store in the country. Headquarters are in New York City....
  • MAD (museum, New York City, New York, United States)
    museum in New York, N.Y., dedicated to the collection and exhibition of contemporary works and objects made from clay, glass, wood, metal, and fibre. It emphasizes craft, art, and design but is also concerned with the broader subjects of architecture, fashion, interior design, industrial design, performing arts, and technology....
  • Mad (American magazine)
    American publisher who launched Mad magazine (1952), an irreverent monthly with humorous illustrations and writing that satirized mass media, politicians, celebrities, and comic books....
  • MAD (military science)
    ...than a small fraction of its entire territory, and both sides were thus kept subject to the deterrent effect of the other’s strategic forces. This arrangement was seen to reinforce the concept of mutual assured destruction (MAD), in which the prospect of annihilation for both sides would prevent either side from “going nuclear” in the event of a conflict. The very concept o...
  • Mad About You (television program)
    ...role on St. Elsewhere and numerous made-for-television movies. After several failed television series, Hunt was offered the role of Jamie Buchman on Mad About You in 1992. Developed by and costarring Paul Reiser, the comedy followed the ups and downs of a married couple. In addition to acting, for which she received four Golden Globe......
  • Mad Caliph, The (Fāṭimid caliph)
    sixth ruler of the Egyptian Shīʿite Fāṭimid dynasty, noted for his eccentricities and cruelty, especially his persecutions of Christians and Jews. He is held by adherents of the Druze religion to be a divine incarnation....
  • mad cow disease (pathology)
    a fatal neurodegenerative disease of cattle....
  • mad itch (viral disease)
    viral disease mainly of cattle and swine but also affecting sheep, goats, dogs, cats, raccoons, opossums, skunks, and rodents. It is not considered to be a disease of humans. Infected swine lose their appetites and may have convulsive fits. Survivors of the initial attack scratch and are restless. A cow shows infection by rubbing against posts and by licking and biting the affected areas. The itch...
  • Mad Jack Byron (British officer)
    Byron was the son of the handsome and profligate Captain John “Mad Jack” Byron and his second wife, Catherine Gordon, a Scots heiress. After her husband had squandered most of her fortune, Mrs. Byron took her infant son to Aberdeen, Scotland, where they lived in lodgings on a meagre income; the captain died in France in 1791. George Gordon Byron had been born with a clubfoot and......
  • Mad King Ludwig (king of Bavaria)
    eccentric king of Bavaria from 1864 to 1886 and an admirer and patron of the composer Richard Wagner. He brought his territories into the newly founded German Empire (1871) but concerned himself only intermittently with affairs of state, preferring a life of increasingly morbid seclusion and developing a mania for extravagant building projects....
  • Mad Mab (American musician)
    American band leader and saxophonist of the swing jazz era....
  • Mad War (French history)
    ...Duc d’Orléans, the future Louis XII of France; and the States General were convened (1484). When the Beaujeus ignored that assembly’s demand to control taxation and hold regular meetings, the “Mad War” broke out between, on the one side, the crown and, on the other, the Duc d’Orléans and Francis II of Brittany, which ended in a royal victory....
  • Madabā (Jordan)
    town, west-central Jordan. It is situated on a highland plain more than 2,500 feet (760 metres) above sea level. The town lies 20 miles (32 km) south of Amman, along a main highway to southern Jordan....
  • Madabā mosaic map (archaeology)
    The town is famous in historical cartography for the Madabā mosaic map, thought to be the oldest surviving map of Palestine and the neighbouring territories. The mosaic map, which formed the floor of one of the many ruined ancient churches in Madabā, was discovered in 1884. The map dates from the 6th century ce, was originally 72 by 23 feet (22 by 7 metres) in size, and...
  • Madabbar, Johannes (Ethiopian bishop)
    ...About 1600, nevertheless, a few substantial works in Geʿez appeared, including Hawi, an enormous theological encyclopaedia translated by Salik of Debre Libanos; a History by Johannes Madabbar, bishop of Nikiu, containing an account of the Arab conquest of Egypt, valuable since the Arab original has been lost; and Fetha Negast (“Justice of the Kings”),.....
  • Madách, Imre (Hungarian poet)
    Hungarian poet whose reputation rests on his ambitious poetic drama Az ember tragediája (1861; The Tragedy of Man). He is often considered to be Hungary’s greatest philosophical poet....
  • Madagascan region (faunal region)
    Madagascar is so different from the continent of Africa that it is generally given equal status as a separate region (Figure 2). Mammalian families shared with the African mainland (Paleotropical realm) include Tenrecidae (tenrecs and otter shrews) and Hippopotamidae (hippopotamuses, which have recently become extinct in Madagascar). Madagascar also shares some groups with the Neotropical......
  • Madagascar
    country lying off the southeastern coast of Africa. It occupies the fourth largest island in the world, after Greenland, New Guinea, and Borneo. Located in the southwestern Indian Ocean, it is separated from the African coast by the 250-mile- (400-kilometre-) wide Mozambique Channel....
  • Madagascar, flag of
    ...
  • Madagascar, history of
    History...
  • Madagascar jasmine (plant)
    ...short-stalked flowers grow in clusters from the leaf axils and have a leafy, five-parted calyx and a tubular, five-lobed corolla that is swollen at its base. The best-known member of the genus, the Madagascar jasmine (Marsdenia floribunda), waxflower, or floradora, is a popular greenhouse plant. This woody, twining vine is native to Madagascar. It has leathery, oval leaves that grow up.....
  • Madagascar orchid (orchid)
    ...morganii praedicta, named in honour of its predicted existence by Charles Darwin and Alfred Russel Wallace, exclusively pollinates the Madagascar orchid, Angraecum sesquipedale. The proboscis of this hawk moth is long enough to reach the nectar receptacle of the orchid, which is between 20 and 35 cm (8 and 14 inches) in length....
  • Madagascar periwinkle (plant)
    ...tomato flower rather specifically. These structures enlarge greatly under the influence of the virus and fuse to form huge bladderlike structures that may be 10 times or more the normal size. In the Madagascar periwinkle (Vinca rosea), however, viruses of this type bring about a green colouring in the petals, stamens, and styles; normally the petals are pink and the stamens and styles......
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