/ Dictionary / Index D diadem: Meaning and Definition of Find definitions for: di•a•dem Pronunciation: (dī'u-dem"), [key] — n. a crown. a cloth headband, sometimes adorned with jewels, formerly worn by Oriental kings. royal dignity or authority. —v.t. to adorn with or as if with a diadem; crown. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: diadem (Thesaurus) diadelphous diadic Related Content Daily Word Quiz: supine Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language