/ Dictionary / Index R radio window: Meaning and Definition of Find definitions for: ra'dio win"dow Pronunciation: [key] — Astron. Astron. the range of wavelengths at which the earth's atmosphere is transparent to radio waves. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. radio wave radish Related Content Daily Word Quiz: vertigo Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language