/ Dictionary / Index G gastro-: Meaning and Definition of Find definitions for: gastro- Pronunciation: [key] a combining form meaning “stomach,” used in the formation of compound words: gastrology. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. gastritis gastrocnemius Related Content Daily Word Quiz: sinister Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language