Definition of dementia in English:



  • [mass noun] A chronic or persistent disorder of the mental processes caused by brain disease or injury and marked by memory disorders, personality changes, and impaired reasoning.

    • ‘People with dementia have a degenerative disease of the brain for which there is no cure.’
    • ‘They support people with conditions such as dementia and Alzheimer's disease.’
    • ‘Early-stage dementia or Alzheimer's disease may be associated with gluten antibodies.’
    • ‘The higher homocysteine, the higher your chances of a person contracting dementia.’
    • ‘People with dementia sometimes find it easier to look into memories than fact.’
    mental illness, madness, insanity, derangement, lunacy
    senile dementia, alzheimer's disease, alzheimer's
    softening of the brain
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Late 18th century: from Latin, from demens, dement- out of one's mind.