noun \di-ˈmen(t)-shə, -shē-ə\

medical : a mental illness that causes someone to be unable to think clearly or to understand what is real and what is not real

Full Definition of DEMENTIA

:  a usually progressive condition (as Alzheimer's disease) marked by deteriorated cognitive functioning often with emotional apathy
:  madness, insanity <a fanaticism bordering on dementia>
de·men·tial \-shəl\ adjective

Examples of DEMENTIA

  1. This patient suffers from dementia.
  2. a new study on age-related dementias

Origin of DEMENTIA

Latin, from dement-, demens mad, from de- + ment-, mens mind — more at mind
First Known Use: 1806

Other Psychology Terms

fetish, hypochondria, intelligence, mania, narcissism, neurosis, pathological, psychosis, schadenfreude, subliminal


noun \di-ˈmen-chə\   (Medical Dictionary)

Medical Definition of DEMENTIA

: a usually progressive condition (as Alzheimer's disease) marked by the development of multiple cognitive deficits (as memory impairment, aphasia, and inability to plan and initiate complex behavior)
de·men·tial \-chəl\ adjective


noun    (Concise Encyclopedia)

Chronic, usually progressive deterioration of intellectual functions. Most common in the elderly, it usually begins with short-term-memory loss once thought a normal result of aging but now known to result from Alzheimer disease. Other common causes are Pick disease and vascular disease. Dementia also occurs in Huntington chorea, paresis (see paralysis), and some types of encephalitis. Treatable causes include hypothyroidism (see thyroid gland), other metabolic diseases, and some malignant tumours. Treatment may arrest dementia's progress but usually does not reverse it.


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