psalterium

UK: /sɔːlˈtɪərɪəm/ US: (sôl tēr′ē əm)

WordReference Random House Unabridged Dictionary of American English © 2025

psal•te•ri•um  (sôl tēr′ē əm), n., pl. -te•ri•a (-tēr′ē ə). [Zool.]

1. Zoology the omasum.

• Late Latin psaltērium the Psalter, the folds of the omasum being likened to the leaves of a book
• 1855–60

psal•te′ri•al, adj. 

Collins Concise English Dictionary © HarperCollins Publishers::

psalterium / sɔːlˈtɪərɪəm/ noun ( -teria / -ˈtɪərɪə/)

1. the third compartment of the stomach of ruminants, between the reticulum and abomasum
   Also called: omasum

Etymology: 19th Century: from Latin psaltērium Psalter; from the similarity of its folds to the pages of a book