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.
That side effect was not seen with ALZ-801, which works by preventing amyloid plaques from forming in the first place. Melissa Rudy, FOXNews.com, 30 Oct. 2025 Alzheon's product is meant to keep plaques from forming in the first place, by preventing amyloid proteins from clumping at all. Jon Hamilton, NPR, 29 Oct. 2025 Macrophages, the immune cells responsible for cleanup and repair, flooded into the inflamed tissue and released a protein called serum amyloid A3 (SAA3). New Atlas, 29 Oct. 2025 These two treatments—lecanemab and donanemab—now remove amyloid from people's brains. Hannah Millington, MSNBC Newsweek, 29 Oct. 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 3 Nov. 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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