de·men·tia | \di-ˈmen(t)-shə, -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 \-shəl \ adjective

Examples of dementia in a Sentence

This patient suffers from dementia. a new study on age-related dementias

Recent Examples on the Web

Facilitator will be Adrianne DeVivo, dementia specialist at Hartford HealthCare Center for Healthy Aging. Courant Community, "Community News For The Windham Edition," 12 June 2018 This level of activity helps combat heart disease, stroke, Type 2 diabetes, obesity, dementia and cancer. 100 mg/dl. Cara Rosenbloom,, "Ignore calories and BMI. Here are the health numbers that really matter.," 9 July 2018 This reader is sinking in sadness as her 83-year-old mother struggles with dementia and chronic pain. Veronica Mitchell,, "Ask Veronica — Accepting the truth about dementia-fueled outbursts," 2 July 2018 The silver alert issued for a woman believed to have dementia or some other cognitive impairment has now been canceled. Samantha West, Milwaukee Journal Sentinel, "Silver Alert canceled for 65-year-old Milwaukee woman believed to have dementia or cognitive impairment," 23 June 2018 Reconnecting With Memories In recent years, music therapy has grown in popularity for its seeming ability to help calm people with dementia and reconnect them with their memories. Robert Mccoppin,, "Music Can Call Back Loved Ones Lost In Alzheimer's Darkness," 22 June 2018 One study of thousands of Dutch adults aged 55 and older found those who ate lots of fish were 60% less likely to develop dementia and 70% less likely to develop Alzheimer’s than those who ate diets low in fish. Markham Heid, Time, "Are Omega-3s Good for Your Brain?," 20 June 2018 Willett says that could slash the rates of preliminary death from heart disease, and reduce the incidence of diabetes, dementia and other metabolic diseases. Author: Caitlin Dewey, Anchorage Daily News, "Artificial trans fats, widely linked to heart disease, are officially banned," 19 June 2018 Remember that too much alcohol may actually increase your risk of dementia and affect your sleep and memory. Fiza Pirani, ajc, "How to prevent Alzheimer’s: Sleep, drink wine and exercise, researchers suggest," 11 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

6 Oct 2018

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Time Traveler for dementia

The first known use of dementia was in 1806

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de·men·tia | \di-ˈmen-chə \

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 \ adjective

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Comments on dementia

What made you want to look up dementia? Please tell us where you read or heard it (including the quote, if possible).


a state of commotion or excitement

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