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Greenspan, Alan

(Encyclopedia)Greenspan, Alan, 1926–, American economist, chairman of the Federal Reserve Board (1987–2006), b. New York City. Influenced by the philosophy of Ayn Rand, Greenspan is a strong supporter of the fr...

gonadotropic hormone

(Encyclopedia)gonadotropic hormone gōˌnădətrŏpˈĭk [key] or gonadotropin, any one of three glycoprotein (see protein) hormones released by either the anterior pituitary gland or the placenta (the organ in whi...

flame

(Encyclopedia)flame, phenomenon associated with the chemical reaction of a gas that has been heated above its kindling temperature with some other gas, usually atmospheric oxygen (see combustion). The heat and ligh...

new towns

(Encyclopedia)new towns, planned urban communities in Great Britain, developed by long-term loans from the central government and first authorized by the New Towns Act of 1946. The chief purpose of the act was to r...

Northeast Passage

(Encyclopedia)Northeast Passage, water route along the northern coast of Europe and Asia, between the Atlantic and Pacific oceans. Beginning in the 15th cent., efforts were made to find a new all-water route to Ind...

magnetic levitation

(Encyclopedia)magnetic levitation or maglev măgˈlĕv [key], support and often propulsion of objects or vehicles by the use of magnets. The magnets used in magnetic levitation suspend an object free of contact wit...

mechanized warfare

(Encyclopedia)mechanized warfare, employment of modern mobile attack and defense tactics that depend upon machines, more particularly upon vehicles powered by gasoline and diesel engines. Central to the waging of m...

minimum wage

(Encyclopedia)minimum wage, lowest wage legally permitted in an industry or in a government or other organization. The goal in establishing minimum wages has been to assure wage earners a standard of living above t...

lemming

(Encyclopedia)lemming, name for several species of mouselike rodents related to the voles. All live in arctic or northern regions, inhabiting tundra or open meadows. They frequently nest in underground burrows, par...

parachute

(Encyclopedia)parachute, umbrellalike device designed to retard the descent of a falling body by creating drag as it passes through the air. The development of modern aircraft has led to many experiments in the aer...