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noun thy·la·koid \ˈthī-lə-ˌkȯid\

Definition of thylakoid

  1. :  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

Origin and Etymology of thylakoid

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

First Known Use: 1962

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