yard vs cubic yard

yard and cubic yard both are nouns.

Word	Noun	Adjective	Verb	Adverb
yard	Yes	No	No	No
cubic yard	Yes	No	No	No

As nouns, yard and cubic yard are synonyms defined as:

yard (noun)	cubic yard (noun)
an enclosure for animals (as chicken or livestock)	a unit of volume (as for sand or gravel)
a long horizontal spar tapered at the end and used to support and spread a square sail or lateen
the enclosed land around a house or other building
an area having a network of railway tracks and sidings for storage and maintenance of cars and engines
a tract of land enclosed for particular activities (sometimes paved and usually associated with buildings)
a tract of land where logs are accumulated
a unit of length equal to 3 feet; defined as 91.44 centimeters; originally taken to be the average length of a stride
a unit of volume (as for sand or gravel)
the cardinal number that is the product of 10 and 100