Great Britain vs Lords Temporal

Great Britain and Lords Temporal both are nouns.

Word	Noun	Adjective	Verb	Adverb
Great Britain	Yes	No	No	No
Lords Temporal	Yes	No	No	No

Great Britain (noun)	Lords Temporal (noun)
an island comprising England and Scotland and Wales	the nobility in France and the peerage in Britain
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