Great Britain vs clever clogs

Great Britain and clever clogs both are nouns.

Word	Noun	Adjective	Verb	Adverb
Great Britain	Yes	No	No	No
clever clogs	Yes	No	No	No

Great Britain (noun)	clever clogs (noun)
an island comprising England and Scotland and Wales	an intellectual who is ostentatiously and irritatingly knowledgeable
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