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Brahe, Tycho

(Encyclopedia)Brahe, Tycho tīˈkō brä [key], 1546–1601, Danish astronomer. The most prominent astronomer of the late 16th cent., he paved the way for future discoveries by improving instruments and by his prec...

smart weapon

(Encyclopedia)smart weapon, missile or steerable bomb equipped with a laser, television, or satellite guidance system. Smart weapons, which use guidance systems that rely on external assistance, are distinguished f...

GCA

(Encyclopedia)GCA, ground-controlled approach: see instrument-landing system. ...

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...

psychosomatic medicine

(Encyclopedia)psychosomatic medicine sīˌkōsōmătˈĭk [key], study and treatment of those emotional disturbances that are manifested as physical disorders. The term psychosomatic emphasizes essential unity of t...

sharecropping

(Encyclopedia)sharecropping, an agricultural system in which a landowner allows a tenant to use their land in return for a share of the crop produced. In the United S...

peonage

(Encyclopedia)peonage pēˈənĭj [key], system of involuntary servitude based on the indebtedness of the laborer (the peon) to his creditor. It was prevalent in Spanish America, especially in Mexico, Guatemala, Ec...

radio-frequency identification

(Encyclopedia)radio-frequency identification (RFID), a technology that uses radio waves to transmit data and uniquely identify an animal, person, or thing. An RFID system typically consists of a tag and a reader. T...

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