/ Dictionary / Index R radiatus: Meaning and Definition of Find definitions for: ra•di•a•tus Pronunciation: (rā"dē-ā'tus), [key] — adj. Meteorol. (of a cloud) having bands that appear to converge toward a point on the horizon. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. radiator grille radical Related Content Daily Word Quiz: modify Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language