cubic content unit vs volume unit

cubic content unit and volume unit both are nouns.

Word	Noun	Adjective	Verb	Adverb
cubic content unit	Yes	No	No	No
volume unit	Yes	No	No	No

As nouns, cubic content unit and volume unit are synonyms defined as:

cubic content unit and volume unit: a unit of measurement of volume or capacity

Other synonyms of cubic content unit include capacity measure, capacity unit, cubage unit, cubature unit, cubic measure, displacement unit.

cubic content unit (noun)	volume unit (noun)
a unit of measurement of volume or capacity	a unit of measurement of volume or capacity