/ Dictionary / Index Q quindecagon: Meaning and Definition of Find definitions for: quin•dec•a•gon Pronunciation: (kwin-dek'u-gon"), [key] — n. Geom. a polygon having 15 angles and 15 sides. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Quincy quindecennial Related Content Daily Word Quiz: cautious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language