UK vs Battle of Britain

UK and Battle of Britain both are nouns.

Word	Noun	Adjective	Verb	Adverb
UK	Yes	No	No	No
Battle of Britain	Yes	No	No	No

UK (noun)	Battle of Britain (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	the prolonged bombardment of British cities by the German Luftwaffe during World War II and the aerial combat that accompanied it