de·​men·​tia | \ di-ˈmen(t)-shə How to pronounce dementia (audio) , -shē-ə \

Definition of dementia

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

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Other Words from dementia

demential \ di-​ˈmen(t)-​shəl How to pronounce dementia (audio) , -​shē-​əl \ adjective

Synonyms & Antonyms for dementia



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Examples of dementia in a Sentence

This patient suffers from dementia. a new study on age-related dementias
Recent Examples on the Web Cousin Evelyn Persico had worried that Ceccarelli, who lives with dementia, might feel abandoned during the pandemic, with her usual visitors barred. Julia Wick, Los Angeles Times, "At 113, she’s California’s oldest native. She got through a tough 2020 and is still going strong," 21 Feb. 2021 Dear Advice Team: My father is currently living with dementia. Chronicle Advice Team, San Francisco Chronicle, "My father has dementia. How do I keep him engaged and safe during the pandemic?," 4 Feb. 2021 Remembering Long Enough, based on her mother’s experience with dementia. Manuel Mendoza, Dallas News, "Undermain Theatre to stream ambitious season of shows from its legendary Deep Ellum basement," 4 Feb. 2021 While in Washington members of Congress readied gas masks, in West Roxbury a veteran with dementia wandered the hallways of the floor. Hanna Krueger,, "Two patients, one week in the hospital, and a world of change," 23 Jan. 2021 According to her family, Gray has been diagnosed with dementia and needs constant supervision. William Thornton |, al, "Missing Decatur woman found," 14 Jan. 2021 Prosecutors at the time declined an offer to speak to the physicians who had diagnosed Mr. Brockman with dementia, attorney Jason Varnado of Jones Day said at the hearing. Dave Michaels, WSJ, "Former CEO Accused of Biggest Tax Fraud Ever Wins Transfer of Case to Houston," 4 Jan. 2021 That premise could have made for a straightforward mystery-thriller, but for this detail: Maud is struggling with dementia. New York Times, "What’s on TV This Week: ‘Jimmy Carter Rock & Roll President’ and ‘RuPaul’s Drag Race’," 28 Dec. 2020 The decorations were printed up and delivered to Grace Point Place, a memory care facility that serves individuals challenged with dementia. Daily Southtown Staff,, "Community news: Schools, groups and others participate in holiday giveaways," 24 Dec. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'dementia.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of dementia

1806, in the meaning defined at sense 1

History and Etymology for dementia

Latin, from dement-, demens mad, from de- + ment-, mens mind — more at mind

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Time Traveler for dementia

Time Traveler

The first known use of dementia was in 1806

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Statistics for dementia

Last Updated

26 Feb 2021

Cite this Entry

“Dementia.” Dictionary, Merriam-Webster, Accessed 3 Mar. 2021.

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de·​men·​tia | \ di-ˈmen-chə How to pronounce dementia (audio) \

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)

Other Words from dementia

demential \ -​chəl How to pronounce dementia (audio) \ adjective

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