/ Dictionary / Index V vitamin G: Meaning and Definition of Find definitions for: vitamin G Pronunciation: [key] riboflavin. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. vitamin E vitamin H Related Content Daily Word Quiz: perspicacious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language