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.
Until recently, diagnosing Alzheimer’s required a medical history and exam as well as postmortem evidence of two abnormal proteins associated with the disease called amyloid and tau. — Anand Kumar, The Conversation, 26 Aug. 2026 Instead of using p-tau217 and amyloid blood tests for diagnosis, Isaacson runs them to look for clues on how people are responding to treatment and lifestyle changes. — Sandee Lamotte, CNN Money, 24 Aug. 2026 What's more, the results remained consistent even in patients with comorbidities like chronic kidney disease and diabetes, which can distort plasma amyloid samples. — New Atlas, 24 Aug. 2026 The Food and Drug Administration has approved a new blood test for Alzheimer’s that can detect a presence in the brain of amyloid plaque, which has been considered a key indicator of the disease. — Christopher Rowland, Washington Post, 24 Aug. 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
See all Nearby Words

Cite this Entry

“Amyloid.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/amyloid. Accessed 2 Sep. 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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