cubic content unit vs displacement unit

cubic content unit and displacement unit both are nouns.

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

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

cubic content unit and displacement 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, volume unit.

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