UK vs pub

UK and pub both are nouns.

Word	Noun	Adjective	Verb	Adverb
UK	Yes	No	No	No
pub	Yes	No	No	No

UK (noun)	pub (noun)
a monarchy in northwestern Europe occupying most of the British Isles; divided into England and Scotland and Wales and Northern Ireland; `Great Britain' is often used loosely to refer to the United Kingdom	tavern consisting of a building with a bar and public rooms; often provides light meals