/ Dictionary / Index G guanosine: Meaning and Definition of Find definitions for: gua•no•sine Pronunciation: (gwä'nu-sēn", -sin), [key] — n. Biochem. a ribonucleoside component of ribonucleic acid, comprising ribose and guanine. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: guanosine (Thesaurus) guano guanosine monophosphate Related Content Daily Word Quiz: neologism Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language