/ Dictionary / Index R rayless: Meaning and Definition of Find definitions for: ray•less Pronunciation: (rā'lis), [key] — adj. lacking rays or raylike parts. unlit, dark, or gloomy: a rayless cave. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: rayless (Thesaurus) Rayleigh wave Raymond Related Content Daily Word Quiz: clairvoyant Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language