/ Dictionary / Index R rottenstone: Meaning and Definition of Find definitions for: rot•ten•stone Pronunciation: (rot'n-stōn"), [key] — n. a friable stone resulting from the decomposition of a siliceous limestone, used as a powder for polishing metals. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: rottenstone (Thesaurus) rotten ice rotter Related Content Daily Word Quiz: placid Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language