/ Dictionary / Index R ribonucleic acid: Meaning and Definition of Find definitions for: ri'bo•nu•cle'ic ac'id Pronunciation: (rī'bō-n-klē'ik, -klā'-, -ny-, rī"-), [key] — Biochem. Biochem. See Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. ribonuclease ribonucleoprotein Related Content Daily Word Quiz: dissonant Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language