SAS vs Great Britain

SAS and Great Britain both are nouns.

Word	Noun	Adjective	Verb	Adverb
SAS	Yes	No	No	No
Great Britain	Yes	No	No	No

SAS (noun)	Great Britain (noun)
a specialist regiment of the British army that is trained in commando techniques of warfare and used in clandestine operations (especially against terrorist groups)	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