nan vs U.K.

nan and U.K. both are nouns.

Word	Noun	Adjective	Verb	Adverb
nan	Yes	No	No	No
U.K.	Yes	No	No	No

nan (noun)	U.K. (noun)
leavened bread baked in a clay oven in India; usually shaped like a teardrop	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
your grandmother
the mother of your father or mother