Mg

Chemical element, one of the alkaline earth metals, chemical symbol Mg, atomic number 12. The silvery white metal does not occur free in nature, but compounds such as the sulfate (Epsom salts), oxide (magnesia), and carbonate (magnesite) have long been known. The metal, which burns in air with a bright white light, is used in photographic flash devices, bombs, flares, and pyrotechnics; it is also a component of lightweight alloys for aircraft, spacecraft, cars, machinery, and tools. The compounds, in which it has valence 2, are used as insulators and refractories and in fertilizers, cement, rubber, plastics, foods, and pharmaceuticals (antacids, purgatives, laxatives). Magnesium is an essential element in human nutrition; it is the cofactor in enzymes of carbohydrate metabolism and in chlorophyll.

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• Magnesium (Mg), the element
• Milligram (mg) an SI unit of mass, 1/1,000th of a gram (base unit of mass)
• Megagram (Mg) an SI unit of mass 10⁶ of a gram
• Myasthenia gravis (MG), an autoimmune disease
• mg (editor) (mg), Emacs-compatible Unix text editor
• Malagasy language (mg), the national language of Madagascar
• Master Grade (MG), a classification of Gundam plastic models
• Main gauche (m.g., French), indicating "left hand" in piano music
• Minas Gerais (MG), a Brazilian state
• .mg, the Internet country code top-level domain for MadagascarBusiness
• MG Cars (1924–), British automobile manufacturer, now part of China's Nanjing Automobile Group
• Champion Air (MG) (1995–), previously MGM Grand Air, American charter airline with IATA code MGEntertainment
• Match Game (MG) (1962–1969; 1973–1979; 1983–1984; 1990–1991), American television game show
• Mechagodzilla, a fictional character from various films in the Godzilla series
• Memphis Group (M.G.), from the band Booker T. & the M.G.'s fronted by Booker T. Jones
• The MG's (album), an album recorded by Booker T.'s band
• Metal Gear (series), (MG), a video game series directed by Hideo Kojima
• Metal Gear, the first game in the series
• Mother Goose, character and poem
• MG (The Perhapanauts), a character in The Perhapanauts comics
• Meg Griffin a character on Family Guy voiced by Mila KunisMilitary
• Machine gun (MG), typically used as a prefix for model designations (for example "MG42" and "MG3")
• Major General (MG), a military rank used by many countries; the specific "MG" abbreviation is used in the United States
• Medal for Gallantry (MG), Australian military decoration, introduced in 1991