The ending of a tiny airway in the lung, where the alveoli (air sacs) are located. In anatomy, an acinus is a round cluster of cells, usually epithelial cells, that looks somewhat like a knobby berry. The word "acinus" means "berry" in Latin. (The plural is "acini".) There are also acini, round clusters of epithelial c [..]

a small sac-like dilatation, e.g. in the lung the basic unit of gas exchange, each acinus is supplied by a single terminal bronchiole; in the liver, the smallest functional unit.

A small group of cells arranged in a "grape-like" cluster. A classical example is the arrangement of pancreatic exocrine cells, but the term is also applied to larger groups of cells, as in the liver.

A small lobe of a compound gland or a saclike cavity at the termination of a passage. acoelomate

(n) one of the small drupes making up an aggregate or multiple fruit like a blackberry(n) one of the small sacs or saclike dilations in a compound gland

N M grape; ivyberry or other small berry; pip| (grape) pit/seed

Origin: L, grape, grapestone. 1. <botany> One of the small grains or drupelets which make up some kinds of fruit, as the blackberry, raspberry, etc. 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. [..]

A cluster of alveoli at the end of a tiny respiratory airway in the lung.