thy·​la·​koid ˈthī-lə-ˌkȯid How to pronounce thylakoid (audio)
: any of the membranous disks of lamellae within plant chloroplasts that are composed of protein and lipid and are the sites of the photochemical reactions of photosynthesis

Example Sentences

Recent Examples on the Web Spinach is a source of thylakoids, the chlorophyll-bearing parts of green leaves. Lisa Drayer, CNN, 8 Mar. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'thylakoid.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Word History


International Scientific Vocabulary thylak- (from Greek thylakos sack) + -oid

First Known Use

1962, in the meaning defined above

Time Traveler
The first known use of thylakoid was in 1962

Dictionary Entries Near thylakoid

Cite this Entry

“Thylakoid.” Dictionary, Merriam-Webster, Accessed 25 Mar. 2023.

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