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triangle , in mathematics

(Encyclopedia)triangle, in mathematics, plane figure bounded by three straight lines, the sides, which intersect at three points called the vertices. Any one of the sides may be considered the base of the triangle....

triangle , in music

(Encyclopedia)triangle, in music, percussion instrument consisting of a steel rod bent into a triangle, open at one angle, and struck with a steel rod. Only since the end of the 18th cent. has it been an orchestral...

thorn , in botany

(Encyclopedia)thorn, sharp-pointed projection on some plants, usually protective in function. Botanically, thorns are distinguished as modified stems (as in the honey locust and hawthorn) from spines, which are mod...

Regulus, in astronomy

(Encyclopedia)Regulus rĕgˈyələs [key], brightest star in the constellation Leo; Bayer designation Alpha Leonis; 1992 position R.A. 10h08m, Dec. +12°00′. A bluish-white main-sequence star of spectral class B7...

resistance, in biology

(Encyclopedia)resistance, in biology: see immunity. ...

resistance, in psychiatry

(Encyclopedia)resistance, in psychiatry: see psychoanalysis. ...

resistance, in electricity

(Encyclopedia)resistance, property of an electric conductor by which it opposes a flow of electricity and dissipates electrical energy away from the circuit, usually as heat. Optimum resistance is provided by a con...

resonance, in acoustics

(Encyclopedia)resonance, in acoustics: see vibration. ...

resonance, in chemistry

(Encyclopedia)resonance, in chemistry: see chemical bond. ...

restoration, in art

(Encyclopedia)restoration, in art: see art conservation and restoration. ...