/ Dictionary / Index F flow breccia: Meaning and Definition of Find definitions for: flow' brec"cia Pronunciation: [key] — Petrol. Petrol. a volcanic breccia that has solidified from a lava flow. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. flowback flow chart Related Content Daily Word Quiz: panacea Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language