Alzheimer's disease

noun

Alz·​hei·​mer's disease ˈälts-ˌhī-mərz- How to pronounce Alzheimer's disease (audio) ˈalts- How to pronounce Alzheimer's disease (audio) ˈȯlts- How to pronounce Alzheimer's disease (audio)
variants or less commonly Alzheimer disease
ˈälts-ˌhī-mər- How to pronounce Alzheimer's disease (audio)
ˈalts-,
ˈȯlts-
or Alzheimer's
: a degenerative brain disease of unknown cause that is the most common form of dementia, that usually starts in late middle age or in old age, that results in progressive memory loss, impaired thinking, disorientation, and changes in personality and mood, and that is marked histologically by the degeneration of brain neurons especially in the cerebral cortex and by the presence of neurofibrillary tangles and plaques containing beta-amyloid
Behavioral problems, such as mood swings and agitation, may also be a part of the progression of Alzheimer's disease.Allan Perel
… the ability to differentiate normal aging-related memory changes from the impairments associated with dementia, including Alzheimer diseaseC. Munro Cullum
… researchers in California have created mice carrying the gene for beta-amyloid protein, the principal component of the plaques riddling the brains of people with Alzheimer's.Charlene Crabb

Note: Alzheimer's is often used before another noun.

Alzheimer's patients
abbreviation AD

Examples of Alzheimer's disease in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
This is not due to aging itself, but rather to older adults being more likely to take medications that dry their mouths or have conditions that can cause dry mouth, such as dehydration, like diabetes, Alzheimer's disease, and Parkinson's disease.3 2. Lana Barhum, Verywell Health, 6 June 2025 Researchers found that sticking to the MIND diet—a hybrid of the Mediterranean and DASH (Dietary Approaches to Stop Hypertension) diets—were significantly less likely to develop Alzheimer's disease and related dementias. Alex Backus, MSNBC Newsweek, 5 June 2025 Phil Robertson was diagnosed with Alzheimer's disease in December 2024 and died five months later at the age of 79. Ryan Coleman, EW.com, 2 June 2025 The findings come out of a new collaboration between scientists at Washington University School of Medicine in St. Louis (WashU Medicine) and Japanese drug company Eisai, which established a research department in 2022 to find novel Alzheimer's disease preventions and treatments. Bronwyn Thompson, New Atlas, 1 June 2025 See All Example Sentences for Alzheimer's disease

Word History

Etymology

Alois Alzheimer †1915 German physician

First Known Use

1911, in the meaning defined above

Time Traveler
The first known use of Alzheimer's disease was in 1911

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Cite this Entry

“Alzheimer's disease.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Alzheimer%27s%20disease. Accessed 14 Jun. 2025.

Kids Definition

Alzheimer's disease

noun
Alz·​hei·​mer's disease ˈälts-ˌhī-mərz How to pronounce Alzheimer's disease (audio) ˈalts- How to pronounce Alzheimer's disease (audio)
: a brain disease of later life that is characterized by changes in brain tissue with gradual loss of memory and mental abilities

called also Alzheimer's

Medical Definition

Alzheimer's disease

noun
Alz·​hei·​mer's disease ˈälts-ˌhī-mərz- How to pronounce Alzheimer's disease (audio) ˈȯlts- How to pronounce Alzheimer's disease (audio) ˈalts- How to pronounce Alzheimer's disease (audio) ˈalz- How to pronounce Alzheimer's disease (audio)
variants also Alzheimer disease or Alzheimer's
: a degenerative brain disease of unknown cause that is the most common form of dementia, that usually starts in late middle age or in old age, that results in progressive memory loss, impaired thinking, disorientation, and changes in personality and mood, that leads in advanced cases to a profound decline in cognitive and physical functioning, and that is marked histologically by the degeneration of brain neurons especially in the cerebral cortex and by the presence of neurofibrillary tangles and plaques containing beta-amyloid
Behavioral problems, such as mood swings and agitation, may also be a part of the progression of Alzheimer's disease.Allan Perel, The Staten Island (New York) Advance
Alzheimer disease (AD) is the most common cause of dementia, affecting more than 15 million individuals worldwide.Niklas Mattsson et al., The Journal of the American Medical Association
… researchers in California have created mice carrying the gene for beta-amyloid protein, the principal component of the plaques riddling the brains of people with Alzheimer's.Charlene Crabb, U.S. News & World Report
abbreviation AD

More from Merriam-Webster on Alzheimer's disease

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