lollipop lady vs Great Britain

lollipop lady and Great Britain both are nouns.

Word	Noun	Adjective	Verb	Adverb
lollipop lady	Yes	No	No	No
Great Britain	Yes	No	No	No

lollipop lady (noun)	Great Britain (noun)
a woman hired to help children cross a road safely near a school	an island comprising England and Scotland and Wales
	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