subcompact vs auto

subcompact and auto both are nouns.

Word	Noun	Adjective	Verb	Adverb
subcompact	Yes	No	No	No
auto	Yes	No	No	No

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

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

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

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