/ Dictionary / Index E enneagon: Meaning and Definition of Find definitions for: en•ne•a•gon Pronunciation: (en'ē-u-gon"), [key] — n. nonagon. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. ennead enneahedron Related Content Daily Word Quiz: paradox Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language