U.K. vs hall of residence

U.K. and hall of residence both are nouns.

Word	Noun	Adjective	Verb	Adverb
U.K.	Yes	No	No	No
hall of residence	Yes	No	No	No

U.K. (noun)	hall of residence (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	a university dormitory