tunnel vs warren

tunnel and warren both are nouns.

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

As nouns, warren is a hyponym of tunnel; that is, warren is a word with a more specific, narrower meaning than tunnel:

Other hyponyms of tunnel include rabbit warren.

tunnel (noun)	warren (noun)
a passageway through or under something, usually underground (especially one for trains or cars)	a colony of rabbits
a hole made by an animal, usually for shelter	an overcrowded residential area
	a series of connected underground tunnels occupied by rabbits

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