/ Dictionary / Index R rimrock: Meaning and Definition of Find definitions for: rim•rock Pronunciation: (rim'rok"), [key] — n. Geol. rock forming the natural boundary of a plateau or other rise. bedrock forming the natural boundary of a placer or of a gravel deposit. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. rimple Rimsky-Korsakov 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