public house vs tavern

public house and tavern both are nouns.

Word	Noun	Adjective	Verb	Adverb
public house	Yes	No	No	No
tavern	Yes	No	No	No

As nouns, tavern is a hypernym of public house; that is, tavern is a word with a broader meaning than public house:

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

Other hypernyms of public house include tap house.

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