Great Britain vs cottage pie

Great Britain and cottage pie both are nouns.

Word	Noun	Adjective	Verb	Adverb
Great Britain	Yes	No	No	No
cottage pie	Yes	No	No	No

Great Britain (noun)	cottage pie (noun)
an island comprising England and Scotland and Wales	a dish of minced meat topped with mashed potatoes
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