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


aberration, derangement, insanity, lunacy, madness, mania, rage [archaic]


mind, saneness, sanity

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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

The 76-year-old Bears legend is suffering from severe dementia. Kalyn Kahler,, "The Bears at 100: Cheers and a Few Tears," 11 June 2019 But a great year for the 87-year-old Elaine May, who is nominated for her hilarious and heart-piercing performance as a woman struggling with dementia in Kenneth Lonergan’s The Waverly Gallery (a strong contender for Best Revival of a Play). Adam Green, Vogue, "Takeaways From the 2019 Tony Nominations: Downtown Comes to Broadway," 30 Apr. 2019 The country community is reeling after the passing of Earl Thomas Conley, who died on Wednesday morning following a battle with a condition similar to dementia. Megan Stein, Country Living, "Blake Shelton Gives Emotional Tribute to 'Hero' Earl Thomas Conley, Who Died at 77," 11 Apr. 2019 Kobuk, a search and rescue German shepherd, led rescuers to Ruth Brennan, a 77-year-old woman with diabetes and dementia who was lost for two nights without food, water or her medications. Grant Suneson And John Harrington, USA TODAY, "The 25 most heroic dogs in America," 5 July 2018 And the country’s Paro robot, a therapeutic bot that mimics a baby harp seal, is used in nursing homes to engage and entertain dementia patients. James Vincent, The Verge, "Japan’s latest home robot isn’t useful — it’s designed to be loved," 20 Dec. 2018 Click to Read Story To Help Alzheimer’s Patients, a Care Center Recreates the 1950s A new California care facility for dementia patients, was built to resemble a town from the 1950s. Sumathi Reddy, WSJ, "A Lab Tests Playing to Help Children With Autism," 26 Nov. 2018 One study that tried circadian lighting with dementia patients living at home found that caregivers also slept better. Stacey Burling,, "The era of circadian lighting in health care is dawning," 27 June 2018 While drugmaker Avanir Pharmaceuticals has said that many dementia patients suffer from PBA, regulators are concerned that Medicare may be paying for the drug for unapproved and potentially fraudulent uses. Blake Ellis And Melanie Hicken, CNN, "Government issues warning about pill pushed on the elderly," 4 June 2018

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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Statistics for dementia

Last Updated

16 Jun 2019

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Time Traveler for dementia

The first known use of dementia was in 1806

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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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