dementia

noun

de·​men·​tia di-ˈmen(t)-shə How to pronounce dementia (audio)
-shē-ə
1
: a usually progressive condition (such as Alzheimer's disease) marked by the development of multiple cognitive deficits (such as memory impairment, aphasia, and the inability to plan and initiate complex behavior)
dementia is diagnosed only when both memory and another cognitive function are each affected severely enough to interfere with a person's ability to carry out routine daily activities.The Journal of the American Medical Association
2
: madness, insanity
a fanaticism bordering on dementia
demential adjective

Examples of dementia in a Sentence

This patient suffers from dementia. a new study on age-related dementias
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Her grandmother has dementia and has to take 13 different medications. Madison Lammert, Journal Sentinel, 6 Nov. 2024 Her mother, already difficult, is struggling with dementia, hence the road trip, which is meant to resettle her into Robin’s home. Nicholas Quah, Vulture, 26 Oct. 2024 There is no cure for Alzheimer’s, which is the most common form of dementia. Maggie O'Neill, Health, 2 Nov. 2024 Mom, who had dementia, usually went along with whatever Dad told her to do. Carolyn Rosenblatt, Forbes, 2 Nov. 2024 See all Example Sentences for dementia 

Word History

Etymology

borrowed from Latin dēmentia "derangement, insanity, folly," noun derivative of Latin dēment-, dēmens "out of one's mind, frenzied, insane," from dē- de- + -ment, -mens, adjective derivative of ment-, mens "power of reason, mental balance, mind" — more at mind entry 1

First Known Use

1806, in the meaning defined at sense 1

Time Traveler
The first known use of dementia was in 1806

Dictionary Entries Near dementia

Cite this Entry

“Dementia.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/dementia. Accessed 30 Nov. 2024.

Kids Definition

dementia

noun
de·​men·​tia di-ˈmen-chə How to pronounce dementia (audio)
1
: a condition of the brain that is marked especially by a deterioration in the ability to think, reason, or remember
2
: a condition of deteriorating mental functioning

Medical Definition

dementia

noun
de·​men·​tia di-ˈmen-chə How to pronounce dementia (audio)
: 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)
demential adjective

More from Merriam-Webster on dementia

Last Updated: - Updated example sentences
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