Great Britain vs Highway Code

Great Britain and Highway Code both are nouns.

Word	Noun	Adjective	Verb	Adverb
Great Britain	Yes	No	No	No
Highway Code	Yes	No	No	No

Great Britain (noun)	Highway Code (noun)
an island comprising England and Scotland and Wales	the code of rules governing the use of public roads
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