/ Dictionary / Index G gerontic: Meaning and Definition of Find definitions for: ge•ron•tic Pronunciation: (ju-ron'tik), [key] — adj. geriatric. of or pertaining to the last phase in the life cycle of an organism or in the life history of a species. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Geronimo geronto- Related Content Daily Word Quiz: paradox Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language