touring car vs auto

touring car and auto both are nouns.

Word	Noun	Adjective	Verb	Adverb
touring car	Yes	No	No	No
auto	Yes	No	No	No

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

touring car: large open car seating four with folding top
auto: a motor vehicle with four wheels; usually propelled by an internal combustion engine

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

touring car (noun)	auto (noun)
large open car seating four with folding top	a motor vehicle with four wheels; usually propelled by an internal combustion engine