dementia
noun
de·men·tia
di-ˈmen(t)-shə 
-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
The Journal of the American Medical AssociationExamples of dementia in a Sentence
This patient suffers from dementia.
a new study on age-related dementias
Recent Examples on the Web
An Alzheimer's Association report, released April 29, said the total annual cost of caring for people living with Alzheimer’s and other forms of dementia will reach $384 billion in 2025.
—Daniel De Visé, USA Today, 29 Apr. 2025
Alzheimer's disease, the most common cause of dementia, is a neurodegenerative condition that can start developing 20 years before symptoms appear.
—Allen Chang, ABC News, 29 Apr. 2025
Another lead researcher, Taylor Kelty, a postdoctoral fellow in Rector’s lab, noted that previous research has begun to show the link between severe liver dysfunction and a high risk of dementia.
—Angelica Stabile, FOXNews.com, 28 Apr. 2025
Sunday spotlight More than 55 million people worldwide are living with Alzheimer’s disease and other forms of dementia, and that number is expected to nearly triple by 2050.
—Andrew Torgan, CNN Money, 27 Apr. 2025
See All Example Sentences for dementia
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Daniel De Visé, USA Today, 29 Apr. 2025
Alzheimer's disease, the most common cause of dementia, is a neurodegenerative condition that can start developing 20 years before symptoms appear.
—Allen Chang, ABC News, 29 Apr. 2025
Another lead researcher, Taylor Kelty, a postdoctoral fellow in Rector’s lab, noted that previous research has begun to show the link between severe liver dysfunction and a high risk of dementia.
—Angelica Stabile, FOXNews.com, 28 Apr. 2025
Sunday spotlight More than 55 million people worldwide are living with Alzheimer’s disease and other forms of dementia, and that number is expected to nearly triple by 2050.
—Andrew Torgan, CNN Money, 27 Apr. 2025
See All Example Sentences for dementia
Cite this Entry
“Dementia.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/dementia. Accessed 3 May. 2025.
Copy CitationKids Definition
dementia
noun
de·men·tia
di-ˈmen-chə
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
: 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)
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