from The American Heritage® Dictionary of the English Language, 5th Edition.

  • noun Deterioration of intellectual faculties, such as memory, concentration, and judgment, resulting from an organic disease or a disorder of the brain. It is sometimes accompanied by emotional disturbance and personality changes.

from The Century Dictionary.

  • noun An extremely low condition of the mental function; profound general mental incapacity.

from the GNU version of the Collaborative International Dictionary of English.

  • noun Insanity; madness; esp. that form which consists in weakness or total loss of thought and reason; mental imbecility; idiocy.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • noun pathology A progressive decline in cognitive function due to damage or disease in the brain beyond what might be expected from normal aging. Areas particularly affected include memory, attention, judgement, language and problem solving.
  • noun madness or insanity

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • noun mental deterioration of organic or functional origin


from The American Heritage® Dictionary of the English Language, 4th Edition

[Latin dēmentia, madness, from dēmēns, dēment-, senseless; see dement.]


The word dementia has been adopted by Zita Christian.

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  • His father had developed dementia and began to lose memories of even his family.

    May 9, 2011

  • "If we ask Sheila then we can't ask Ron. If I have kippers now then it's quiche for tea. Four score years is about all the ifs and thens you can take. Dementia's the sane realisation you just can't be doing with all that any more". "The Last Werewolf" by Glen Duncan

    February 25, 2012