sugár

Etymology
. The verb is in origin an onomatopoeia corresponding to English rustle, so the original meaning of  may have been a rustling object. The several other current meanings are the result of a name transfer process. The geometry sense of radius was patterned after Latin, compare.

Noun

 * 1)  ray, beam
 * 2)  jet, spurt, stream
 * 3)  radius a line segment between any point of a circle or sphere and its center

Declension
or (in archaic or poetic style)