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guided missile

(Encyclopedia)guided missile, self-propelled, unmanned space or air vehicle carrying an explosive warhead. Its path can be adjusted during flight, either by automatic self-contained controls or remote human control...

air navigation

(Encyclopedia)air navigation, science and technology of determining the position of an aircraft with respect to the surface of the earth and accurately maintaining a desired course (see navigation). Basic to air ...

mutation

(Encyclopedia)mutation, in biology, a sudden, random change in a gene, or unit of hereditary material, that can alter an inheritable characteristic. Most mutations are not beneficial, since any change in the delica...

solid waste

(Encyclopedia)solid waste, discarded materials other than fluids. In the United States in 1996, nearly 210 million tons—about 4.3 lb. (2 kg) per person daily (up from 2.7 lb./1.2 kg in 1960)—were collected and ...

wheat

(Encyclopedia)wheat, cereal plant of the genus Triticum of the family Poaceae (grass family), a major food and an important commodity on the world grain market. Wheat is classified in the division Magnoliophyta, ...

balloon

(Encyclopedia)balloon, lighter-than-air craft without a propulsion system, lifted by inflation of one or more containers with a gas lighter than air or with heated air. During flight, altitude may be gained by disc...

airship

(Encyclopedia)airship, an aircraft that consists of a cigar-shaped gas bag, or envelope, filled with a lighter-than-air gas to provide lift, a propulsion system, a steering mechanism, and a gondola accommodating pa...

Arab Spring

(Encyclopedia)Arab Spring, in modern North African and Middle Eastern history, antigovernment demonstrations and uprisings that, from late 2010, swept many of the regions' Arab nations. Arising in large part in rea...

Mozambique, country, Africa

(Encyclopedia)CE5 Mozambique mōˌzəmbēkˈ [key], officially Republic of Mozambique, republic (2015 est. pop. 25,303,000), 302,659 sq mi (784,090 sq km), SE Africa. It borders on the Indian Ocean in the east; ...

eye

(Encyclopedia)CE5 Cross section of human eye eye, organ of vision and light perception. In humans the eye is of the camera type, with an iris diaphragm and variable focusing, or accommodation. Other types of ey...