auto vs tunnel

auto and tunnel both are nouns.

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

auto (noun)	tunnel (noun)
a motor vehicle with four wheels; usually propelled by an internal combustion engine	a passageway through or under something, usually underground (especially one for trains or cars)
	a hole made by an animal, usually for shelter

auto (verb)	tunnel (verb)
	force a way through
	move through by or as by digging