pub vs public house

pub and public house both are nouns.

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

As nouns, pub and public house are synonyms defined as:

pub and public house: tavern consisting of a building with a bar and public rooms; often provides light meals

Other synonyms of pub include gin mill, pothouse, saloon, taphouse.

pub (noun)	public house (noun)
tavern consisting of a building with a bar and public rooms; often provides light meals	tavern consisting of a building with a bar and public rooms; often provides light meals