acinus

Etymology

From Latin acinus (“grape, grape-stone”); the histopathologic sense comes figuratively from the fancied resemblance (on microscopy) of acinic cells (acinar cells) to bunches of drupelets, berries, or grapes.

noun

1. (botany) One of the small grains or drupelets which make up some kinds of fruit, as the blackberry, raspberry, etc.
   Coordinate term: vesicle
2. (botany) A grape-stone.
3. (anatomy) One of the granular masses which constitute a racemose or compound gland, as the pancreas; also, one of the saccular recesses in the lobules of a racemose gland.
   Their smallest lobules were called acini, a term which has also been used to denote the saccular recesses in the lobules […] 1828, Jones Quain, Quain's elements of anatomy