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.
Previous research suggested caffeine may help reduce the buildup of amyloid-beta, a protein linked to Alzheimer's disease. — Lauren Pastrana, CBS News, 29 June 2026 This process flushes out toxic metabolic byproducts, including amyloid-beta. — Julian Hayes Ii, Forbes.com, 27 May 2026 By serving as a test group for experimental amyloid drugs, DIAN families helped pave the way for lecanemab and donanemab the two amyloid drugs now on the market. — Jon Hamilton, NPR, 7 May 2026 During deep sleep, the brain’s glymphatic system clears metabolic waste including proteins linked to Alzheimer’s disease, and research shows even one night of deprivation can increase amyloid deposits in the brain. — Allison Palmer, Charlotte Observer, 19 May 2026 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

Phrases Containing amyloid

Rhymes for amyloid

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Browse Nearby Words

amylograph
amyloid
amyloid beta
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Cite this Entry

“Amyloid.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/amyloid. Accessed 8 Jul. 2026.

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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

Britannica.com: Encyclopedia article about amyloid

Last Updated: - Updated example sentences
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