Granum
/ˈɡreɪnəm/noun
A granule, especially one of the stacks of thylakoids found inside a chloroplast.
Did you know?In botany, the plural of granum is the Latin-derived “grana,” and the name reflects the stacked structures’ resemblance to a pile of grains.
Etymological Timeline
Proto-Indo-European
PIE
*ǵr̥H-nóm
“Grain or seed; a reconstructed term connected with harvested produce.”
Proto-Italic
Proto-Italic
*grānom
“Grain or seed.”
Classical Latin
Latin
grānum
“A grain, seed, small particle, or kernel.”
Late Latin
Latin
granum
“A grain or small granular unit; the word remained productive in scientific terminology.”
18th Century
Scientific Latin
granum
“A botanical term for a grain-like body or granule.”
Modern English
English
granum
“A stack of thylakoids within a chloroplast; plural grana.”