compact car vs motorcar

compact car and motorcar both are nouns.

Word	Noun	Adjective	Verb	Adverb
compact car	Yes	No	No	No
motorcar	Yes	No	No	No

As nouns, motorcar is a hypernym of compact car; that is, motorcar is a word with a broader meaning than compact car:

compact car: a small and economical car
motorcar: a motor vehicle with four wheels; usually propelled by an internal combustion engine

Other hypernyms of compact car include auto, automobile, car, machine.

compact car (noun)	motorcar (noun)
a small and economical car	a motor vehicle with four wheels; usually propelled by an internal combustion engine