Ordnance Survey vs Great Britain

Ordnance Survey and Great Britain both are nouns.

Word	Noun	Adjective	Verb	Adverb
Ordnance Survey	Yes	No	No	No
Great Britain	Yes	No	No	No

Ordnance Survey (noun)	Great Britain (noun)
the official cartography agency of the British government	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