subcompact car vs automobile

subcompact car and automobile both are nouns.

Word	Noun	Adjective	Verb	Adverb
subcompact car	Yes	No	No	No
automobile	Yes	No	Yes	No

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

subcompact car: a car smaller than a compact car
automobile: a motor vehicle with four wheels; usually propelled by an internal combustion engine

Other hypernyms of subcompact car include auto, car, machine, motorcar.

subcompact car (noun)	automobile (noun)
a car smaller than a compact car	a motor vehicle with four wheels; usually propelled by an internal combustion engine

subcompact car (verb)	automobile (verb)
	travel in an automobile