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n. pl. ab·o·ma·sa (-sə)
The fourth division of the stomach in ruminant animals, such as cows, sheep, and deer, in which digestion takes place.

[New Latin abomāsum : Latin ab-, ab- + Latin omāsum, tripe; see omasum.]

ab′o·ma′sal (-səl) adj.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(ˌæbəˈmeɪsəm) or


n, pl -sa (-sə) or -si (-saɪ)
(Zoology) the fourth and last compartment of the stomach of ruminants, which receives and digests food from the psalterium and passes it on to the small intestine
[C18: New Latin, from ab-1 + omāsum bullock's tripe]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˌæb əˈmeɪ səm)

n., pl. -sa (-sə).
the fourth or true stomach of the cow and other ruminants, from which partially fermented and digested food is passed to the small intestine.
[1700–10; < New Latin; see ab-, omasum]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.


The fourth division of the stomach in ruminant animals, and the only one having glands that secrete acids and enzymes for digestion. It corresponds anatomically to the stomachs of other mammals. See more at ruminant.
The American Heritage® Student Science Dictionary, Second Edition. Copyright © 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.abomasum - the fourth compartment of the stomach of a ruminantabomasum - the fourth compartment of the stomach of a ruminant; the one where digestion takes place
ruminant - any of various cud-chewing hoofed mammals having a stomach divided into four (occasionally three) compartments
stomach, tum, tummy, breadbasket - an enlarged and muscular saclike organ of the alimentary canal; the principal organ of digestion
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
References in periodicals archive ?
The cow's abomasum - its fourth stomach - had slipped.
The abomasum of freshly slaughtered goat was achieved from local slaughterhouse.
Their four-chamber stomachs cause them to take lengthy afternoon naps, while the rumen processes contents from the stomach or abomasum. But that is where much of the resemblance stops.
The stomach complex was calculated as the digesta-free sum of the weights of the rumen, reticulum, omasum and abomasum. The weights of the heart and lungs, and the weights of liver and spleen were recorded together.
The sum of empty rumen, reticulum, omasum and abomasum weight was 4% of bovine EBW.
Clarifide Plus gives producers genomic predictions for wellness traits that directly indicate the genetic risk for the six most common and costly animal health diseases: mastitis, lameness, metritis, retained placenta, displaced abomasum and ketosis.
We found watery and bloody gastrointestinal contents from the abomasum to the rectum (deer no.
The contents of the abomasum and small and large intestines were yellowish to light brown in color, and were greasy and liquefied.
Some of the early research that investigated the relationship between multiple diseases and documented the association of clinical hypocalcemia with increased risk of developing several other common post-partum diseases, such as mastitis, retained placenta, metritis and displaced abomasum (Mulligan et al., 2006 and Goff, 2008).
Whole stomach and its various parts (Rumen, reticulum, omasum and abomasum) were isolated from the rest of the viscera, emptied and washed with cold phosphate buffer solution (PBS) and then weighed.
Goats have four "stomachs." Their food moves first into the rumen (from which it is periodically regurgitated for more "cud chewing"), then to the reticulum, later to the omasum, and finally to the abomasum (which is most like a more sensitive human stomach).
The digestive system lesions involve erosive, ulcerative stomatitis and fibrinohemorrhagic enteritis and hemorrhages in the mucosa of abomasum (Al-Dubaib, 2009).