Word Study
abomasum
CIDE DICTIONARY
abomasum, n. [NL., fr. L. ab + omasum (a Celtic word).].
The fourth or digestive stomach of a ruminant, which leads from the third stomach omasum. See Ruminantia. [1913 Webster]
OXFORD DICTIONARY
abomasum, n. (pl. abomasa) the fourth stomach of a ruminant.
Etymology
mod.L f. AB- + OMASUM
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