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norepinephrine

(Encyclopedia)norepinephrine nôrˌĕpīnĕfˈrən [key], a neurotransmitter in the catecholamine family that mediates chemical communication in the sympathetic nervous system, a branch of the autonomic nervous sys...

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...

European Central Bank

(Encyclopedia)European Central Bank: see under European Monetary System. ...

religion

(Encyclopedia)religion, a system of thought, feeling, and action that is shared by a group and that gives the members an object of devotion; a code of behavior by which individuals may judge the personal and social...

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...

Système International d'Unités

(Encyclopedia)Système International d'Unités (SI): see International System of Units. ...

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...