Acinus

An acinus (adjective: acinar, plural acini) refers to any cluster of cells that resembles a many-lobed "berry," such as a raspberry (acinus is Latin for berry). The berry-shaped termination of an exocrine gland, where the secretion is produced, is acinar in form, as is the alveolar sac containing multiple alveoli in the lungs.

Read more about Acinus:  Exocrine Glands, Lungs