The four compartments into which it is divided are the rumen, reticulum, omasum, and abomasum or true stomach.
"Common Diseases of Farm Animals"
R. A. Craig, D. V. M.
The digestive organ in all ruminant animals consists of four stomachs, or, rather, a capacious pouch, divided by doorways and valves into four compartments, called, in their order of position, the Paunch, the Reticulum, the omasum, and the Abomasum.
"The Book of Household Management"
Mrs. Isabella Beeton