Webster's Revised Unabridged Dictionary · 1913

Acinus

Acinus (as"i*nus) , noun

[Latin, grape, grapestone.]

1.
(a) (Botany) One of the small grains or drupelets which make up some kinds of fruit, as the blackberry, raspberry, etc.
(b)
(Botany) A grapestone.
2.
(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. — Quain