tavern vs gin mill

tavern and gin mill both are nouns.

Word	Noun	Adjective	Verb	Adverb
tavern	Yes	No	No	No
gin mill	Yes	No	No	No

As nouns, gin mill is a hyponym of tavern; that is, gin mill is a word with a more specific, narrower meaning than tavern:

tavern: a building with a bar that is licensed to sell alcoholic drinks
gin mill: tavern consisting of a building with a bar and public rooms; often provides light meals

Other hyponyms of tavern include beer garden, bucket shop, pothouse, pub, public house, saloon, taphouse, rathskeller, shebeen.

tavern (noun)	gin mill (noun)
a building with a bar that is licensed to sell alcoholic drinks	tavern consisting of a building with a bar and public rooms; often provides light meals