United Kingdom of Great Britain and Northern Ireland vs fire watcher

United Kingdom of Great Britain and Northern Ireland and fire watcher both are nouns.

Word	Noun	Adjective	Verb	Adverb
United Kingdom of Great Britain and Northern Ireland	Yes	No	No	No
fire watcher	Yes	No	No	No

United Kingdom of Great Britain and Northern Ireland (noun)	fire watcher (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	(during World War II in Britain) someone whose duty was to watch for fires caused by bombs dropped from the air