Thylakoid
/ˈθaɪ.lə.kɔɪd/noun
A flattened membrane-bound sac inside chloroplasts and cyanobacteria where the light-dependent reactions of photosynthesis occur.
Did you know?The name comes from Ancient Greek for “sack,” reflecting the flattened pouch-like form of the membrane that hosts photosynthetic pigments such as chlorophyll.
Etymological Timeline
Ancient Greek
Greek
thýlakos
“A sack, pouch, or bag”
Ancient Greek
Greek
thýlakoeidēs
“Sack-shaped or resembling a pouch”
19th Century
Scientific Latin
thylakoidēs
“Sack-shaped; a scientific anatomical descriptor”
Early 20th Century
German
Thylakoid
“A sac-like structure associated with chloroplasts”
20th Century
English
thylakoid
“A flattened membrane sac involved in photosynthesis”
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