/ Dictionary / Index M megalomania: Meaning and Definition of Find definitions for: meg•a•lo•ma•ni•a Pronunciation: (meg"u-lō-mā'nē-u), [key] — n. a symptom of mental illness marked by delusions of greatness, wealth, etc. an obsession with doing extravagant or grand things. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: megalomania (Thesaurus) megalocephalic megalomaniac Related Content Daily Word Quiz: tenacious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language