Also found in: Thesaurus, Medical, Encyclopedia.


1. Suffering from dementia.
2. Informal Crazy or foolish.

de·ment′ed·ly adv.
de·ment′ed·ness n.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.dementedness - mental deterioration of organic or functional origin
insanity - relatively permanent disorder of the mind
alcohol amnestic disorder, alcoholic dementia, Korsakoff's psychosis, Korsakoff's syndrome, Korsakov's psychosis, Korsakov's syndrome, polyneuritic psychosis - dementia observed during the last stages of severe chronic alcoholism; involves loss of memory for recent events although long term memory is intact
presenile dementia - dementia with onset before the age of 65
senile dementia, senile psychosis - dementia of the aged; results from degeneration of the brain in the absence of cerebrovascular disease
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
References in periodicals archive ?
[7] The rapidity of dementedness can increase exponentially by aggregate age, and this aging technique in animals is related to a deliberate deterioration of sensory and
The cheer that welcomed one of the bankers of the week started as he surged to the front three out, and grew in dementedness until Monsignor and jockey Norman Williamson drowned in a roar of Istabraq proportions on entering the winner's enclosure.