/ Dictionary / Index F fault plane: Meaning and Definition of Find definitions for: fault' plane" Pronunciation: [key] — Geol. Geol. See under(def. 6). Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. fault line fault scarp Related Content Daily Word Quiz: diligent Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language