S.U.V. vs auto

S.U.V. and auto both are nouns.

Word	Noun	Adjective	Verb	Adverb
S.U.V.	Yes	No	No	No
auto	Yes	No	No	No

As nouns, auto is a hypernym of S.U.V.; that is, auto is a word with a broader meaning than S.U.V.:

S.U.V.: a high-performance four-wheel drive car built on a truck chassis
auto: a motor vehicle with four wheels; usually propelled by an internal combustion engine

Other hypernyms of S.U.V. include automobile, car, machine, motorcar.

S.U.V. (noun)	auto (noun)
a high-performance four-wheel drive car built on a truck chassis	a motor vehicle with four wheels; usually propelled by an internal combustion engine