/ Dictionary / Index D dementia: Meaning and Definition of Find definitions for: de•men•tia Pronunciation: (di-men'shu, -shē-u), [key] — n. Psychiatry. severe impairment or loss of intellectual capacity and personality integration, due to the loss of or damage to neurons in the brain. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: dementia (Thesaurus) démenti dementia praecox Related Content Daily Word Quiz: arid Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language