abdominal cavity vs cavum

abdominal cavity and cavum both are nouns.

Word	Noun	Adjective	Verb	Adverb
abdominal cavity	Yes	No	No	No
cavum	Yes	No	No	No

As nouns, cavum is a hypernym of abdominal cavity; that is, cavum is a word with a broader meaning than abdominal cavity:

abdominal cavity: the cavity containing the major viscera; in mammals it is separated from the thorax by the diaphragm
cavum: (anatomy) a natural hollow or sinus within the body

Other hypernyms of abdominal cavity include bodily cavity, cavity.

abdominal cavity (noun)	cavum (noun)
the cavity containing the major viscera; in mammals it is separated from the thorax by the diaphragm	(anatomy) a natural hollow or sinus within the body