\Ac"i*nus\, n.; pl. {Acini}. [L., grape, grapestone.]
1. (Bot.)
   (a) One of the small grains or drupelets which make up
       some kinds of fruit, as the blackberry, raspberry,
       etc.
   (b) A grapestone.
2. (Anat.) 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.
   --Quain.