/ Dictionary / Index E Epist.: Meaning and Definition of Find definitions for: Epist. Pronunciation: [key] Epistle. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. epispore epistasis Related Content Daily Word Quiz: gregarious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language