Great Britain vs hard shoulder

Great Britain and hard shoulder both are nouns.

Word	Noun	Adjective	Verb	Adverb
Great Britain	Yes	No	No	No
hard shoulder	Yes	No	No	No

Great Britain (noun)	hard shoulder (noun)
an island comprising England and Scotland and Wales	a paved strip beside a motorway (for stopping in emergencies)
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