/ Dictionary / Index F flash flood: Meaning and Definition of Find definitions for: flash' flood' Pronunciation: [key] a sudden and destructive rush of water down a narrow gully or over a sloping surface, caused by heavy rainfall. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: flashflood (Thesaurus) flasher flash-forward 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