/ Dictionary / Index O octagonal: Meaning and Definition of Find definitions for: oc•tag•o•nal Pronunciation: (ok-tag'u-nl), [key] — adj. having eight angles and eight sides. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: octagonal (Thesaurus) octagon octagon house Related Content Daily Word Quiz: fabricate Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language