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 AssociationSynonyms
Examples of dementia in a Sentence
This patient suffers from dementia.
a new study on age-related dementias
Recent Examples on the Web
Older adults whose cholesterol levels change over time might be tied to a greater risk of dementia, according to a new study.
—Dan Perry, Newsweek, 31 Jan. 2025
That pollution comes from many sources, including fossil fuel combustion and wildfire smoke, and has been linked to health risks, including a higher risk of cardiovascular problems and earlier onset of dementia.
—Alejandra Borunda, NPR, 29 Jan. 2025
And young-onset, or early, dementia—which occurs when people develop dementia symptoms before the age of 65—is also on the rise.
—Lauryn Higgins, Flow Space, 28 Jan. 2025
Ultimately, incorporating olive oil into your diet is an easy, delicious way to support brain health and reduce the risk of dementia.
—Sogol Ash, Contributor, CNBC, 28 Jan. 2025
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Dan Perry, Newsweek, 31 Jan. 2025
That pollution comes from many sources, including fossil fuel combustion and wildfire smoke, and has been linked to health risks, including a higher risk of cardiovascular problems and earlier onset of dementia.
—Alejandra Borunda, NPR, 29 Jan. 2025
And young-onset, or early, dementia—which occurs when people develop dementia symptoms before the age of 65—is also on the rise.
—Lauryn Higgins, Flow Space, 28 Jan. 2025
Ultimately, incorporating olive oil into your diet is an easy, delicious way to support brain health and reduce the risk of dementia.
—Sogol Ash, Contributor, CNBC, 28 Jan. 2025
See all Example Sentences for dementia
Dictionary Entries Near dementia
Cite this Entry
“Dementia.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/dementia. Accessed 8 Feb. 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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