Great Britain vs Open University

Great Britain and Open University both are nouns.

Word	Noun	Adjective	Verb	Adverb
Great Britain	Yes	No	No	No
Open University	Yes	No	No	No

Great Britain (noun)	Open University (noun)
an island comprising England and Scotland and Wales	a British university that is open to people without formal academic qualifications and where teaching is by correspondence or broadcasting or summer school
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