Also found in: Dictionary, Thesaurus, Medical, Wikipedia.


The small terminal sac of an acinous gland, lined with secreting cells.
An individual drupelet of a multiple fruit.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



(1) A structural and functional unit or the terminal secretory portion of the salivary, pancreatic, lacteal, sebaceous, or other saccular (alveolar) glands. The acinus is a bubble-like formation of one or more types of gland cells situated on a basement membrane and surrounded by connective tissue, capillaries, and nerve fibers. The apexes of the cells with their microvilli are directed toward the chamber of the acinus into which the secretion is discharged.

(2) A part of the respiratory apparatus in mammals that includes a section of the lung corresponding to the branches of the terminal bronchus—that is, the bronchioles, alveolar passages, and alveoli. One pulmonary lobule consists of 12–18 acini.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
Accordingly, it was anticipated that particle dose in more complex acinus should be orientationally insensitive too.
Each serous acinus was determined randomly by systematic sample method, moving the microscope stage left to right, in a stepwise way.
Among these transition males, a single specimen (Idas 6, Table 1) contained some acini in the dorsal region where oogonia were observed at the periphery along with spermatids, where both gametes were present within the same single acinus (Fig.
The acinus cells are with clear nuclei, chromatin is finely divided.
These cells formed a thick band around the periphery of each acinus and spermatozoa began to accumulate in the lumina of acini [ILLUSTRATION FOR FIGURE 1B-D OMITTED].
Mercer has used serial section reconstruction to make the first precise measurements of some of the lung's tiniest structures, such as an acinus - a cluster of alveoli vented by a single airway.
The terminal portion (adenomere) present in the PG has an acinus (spherical) shape, and is comprised of pure serous cells with a small central lumen.
3A, B), where spermatogonia lays adjacent to the acinus wall and spermatocytes lay near the inner of the wall, followed by spermatids and spermatozoa, located toward the center of the acinus.
These include rigid arches, cribriform spaces, and bulbous papillae involving the acinus entirely or focally.
In 1960 Emery and Mithal introduced the radial count method, which assesses the complexity of the terminal respiratory unit (Acinus).
Pancreatic secretory granule membrane GP2 is a 78 kDa glycoprotein, synthesized in the exocrine part of the pancreas by the acinus cells [19].
It is also suggested that minute channels are present between the demilunes cells and the mucous cells, which join with the lumen of the acinus.