/ Dictionary / Index R ribozyme: Meaning and Definition of Find definitions for: ri•bo•zyme Pronunciation: (rī'bu-zīm"), [key] a segment of RNA that can act as a catalyst. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. ribozo rib roast 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