Breadcrumb Home > Dictionary > Index R R.R.: Meaning and Definition of Find definitions for: R.R. Pronunciation: [key] railroad. Right Reverend. rural route. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. r-quality R-rated TrendingHere are the facts and trivia that people are buzzing about. Biographies: Notable Jewish Religious Leaders Current Events This Week: September 2023 Hispanic Population and the 2010 U.S. Census Preamble of the United Nations Charter The Jewish Calendar ✖ Related Content Daily Word Quiz: parallax Analogy of the Day: Today’s Analogy Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language