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 demential (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 Ebbers was in the middle of a 25-year federal sentence when his daughters began to notice their 6-foot-4 father wither and slip into dementia. Washington Post, "Ponzi scheme king Bernie Madoff, who bilked investors out of billions, seeks medical release from prison," 5 Feb. 2020 Wood had been confined to assisted living facilities for about 13 years before his death and had suffered from advanced stage dementia for nearly a decade, the team statement said. Hollie Silverman, CNN, "Willie Wood, former Packers safety and Hall of Famer, dies at 83," 4 Feb. 2020 But for many, the commercial reminded them of their parents' and grandparents' love stories, and the toll that Alzheimer's and dementia take. Author: Maura Judkis, Sonia Rao, Anchorage Daily News, "The 5 best Super Bowl commercials - and the 5 worst," 3 Feb. 2020 Bedford police are asking for the public’s help in finding a 71-year-old Pennsylvania woman with dementia who went missing while attending a function in town on Saturday. Breanne Kovatch,, "Bedford police looking for missing Pennsylvania woman who has dementia," 2 Feb. 2020 And yet the Buffalo investigators found that the ex-pro athletes, despite their fears, were no more prone to early onset dementia than the ones who played non-contact sports. Ingfei Chen, The New Yorker, "Exactly How Dangerous Is Football?," 1 Feb. 2020 The team took 921 participants without dementia from Rush' Memory and Aging Project, a large ongoing study that began more than 20 years ago. Gary Stix, Scientific American, "What’s in Kale (or a Pear) that Seems to Lower Alzheimer’s Risk?," 30 Jan. 2020 That could complicate studies of certain diseases, says Kriegstein, such as a form of dementia that affects only particular brain regions. Kelly Servick, Science | AAAS, "Lab-grown ‘minibrains’ differ from the real thing in cell subtypes, gene expression," 29 Jan. 2020 Along with contributing to depression and suicide risk, loneliness can lead to heart disease, diabetes and dementia, said Dr. Doug Nemecek, Cigna's chief medical officer for behavioral health. Jayne O'donnell, USA TODAY, "That cushy work-at-home job can lead to social isolation, mental and physical health risks," 24 Jan. 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

10 Feb 2020

Cite this Entry

“Dementia.” Dictionary, Merriam-Webster, Accessed 19 Feb. 2020.

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More Definitions for dementia


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 demential (audio) \ adjective

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