An
acinus (plural,
acini; adjective,
acinar [] or
acinous) refers to any cluster of
cells that resembles a many-lobed "
berry", such as a
raspberry ( 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.