amyloid

noun

am·​y·​loid ˈa-mə-ˌlȯid How to pronounce amyloid (audio)
: a waxy translucent substance consisting primarily of protein that is deposited in some animal organs and tissues under abnormal conditions (such as Alzheimer's disease) compare beta-amyloid
amyloid adjective

Examples of amyloid 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.
Her brain scan detected amyloid plaque, the telltale sign of Alzheimer’s. Jim Taylor, Chicago Tribune, 8 June 2025 The ratio of these substances helps determine the presence of amyloid plaques in the brain. Joshua P. Cohen, Forbes.com, 2 June 2025 In 2019, a PET scan revealed extensive amyloid plaques in Walsh's brain, confirming the diagnosis. Jon Hamilton, NPR, 30 May 2025 This ratio is correlated with the presence or absence of amyloid plaques in the brain, potentially reducing the need for more invasive procedures like PET scans or spinal fluid analysis. Mill Etienne, Forbes.com, 25 May 2025 See All Example Sentences for amyloid

Word History

First Known Use

1866, in the meaning defined above

Time Traveler
The first known use of amyloid was in 1866

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Cite this Entry

“Amyloid.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/amyloid. Accessed 13 Jun. 2025.

Medical Definition

amyloid

noun
am·​y·​loid
ˈam-ə-ˌlȯid
1
: a nonnitrogenous starchy food
2
: a waxy translucent substance consisting primarily of protein that is deposited in some animal organs and tissue under abnormal conditions (as in Alzheimer's disease) see beta-amyloid
amyloid adjective

More from Merriam-Webster on amyloid

Last Updated: - Updated example sentences
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