Great Britain vs doorknob

Great Britain and doorknob both are nouns.

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

Great Britain (noun)	doorknob (noun)
an island comprising England and Scotland and Wales	a knob used to release the catch when opening a door (often called `doorhandle' in Great 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