/ Dictionary / Index F flatus: Meaning and Definition of Find definitions for: fla•tus Pronunciation: (flā'tus), [key] — pl. -tus•es. intestinal gas produced by bacterial action on waste matter in the intestines and composed primarily of hydrogen sulfide and varying amounts of methane. Also called Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: flatus (Thesaurus) flatulent flatware Related Content Daily Word Quiz: belligerent Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language