• synonyms


  1. (in prescriptions) plural of granum.
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Origin of grana

Borrowed into English from Latin around 1890–95


[grey-nuh m]
noun, plural gra·na [grey-nuh] /ˈgreɪ nə/.
  1. (in prescriptions) a grain.
  2. Botany. one of the structural units of a chloroplast in vascular plants, consisting of layers of thylakoids.
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Origin of granum

From Latin
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for grana

Historical Examples of grana

grana in Science


Plural grana (grā)
  1. A stacked membranous structure within the chloroplasts of plants and green algae that contains the chlorophyll and is the site of the light reactions of photosynthesis. The saclike membranes that make up grana are known as thylakoids. See more at chloroplast.
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The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.