/ Dictionary / Index S solar radius: Meaning and Definition of Find definitions for: so'lar ra'dius Pronunciation: [key] the unit, equivalent to the radius of the sun, in which the radii of stars and other celestial objects are given. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. solar prominence solar sail Related Content Daily Word Quiz: eureka Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language