Abomasum

n. fourth stomach in cud chewing animals

The abomasum, also known as the maw, and the rennet-bag, is the fourth and final stomach compartment in ruminants. The normal anatomical location is along ventral midline. It is a secretory stomach similar in anatomy and function as the monogastric stomach. It serves primarily in the acid hydrolysis of microbial and dietary protein, preparing these protein sources for further digestion and absorption in the small intestine.
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Abomasum the fourth compartment of the ruminant stomach. It is an elongated sac, comparable in structure and function to the stomach of nonruminants. [more]Abomasum - Community and Resources

Noun
1. the fourth compartment of the stomach of a ruminant; the one where digestion takes place
(synonym) fourth stomach
(hypernym) stomach, tummy, tum, breadbasket
(part-holonym) ruminant

n. abomasum, fourth stomach in cud chewing animals