UK vs capital

UK and capital both are nouns.

Word	Noun	Adjective	Verb	Adverb
UK	Yes	No	No	No
capital	Yes	Yes	No	No

UK (noun)	capital (noun)
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	the upper part of a column that supports the entablature
	one of the large alphabetic characters used as the first letter in writing or printing proper names and sometimes for emphasis
	a seat of government
	a center that is associated more than any other with some activity or product
	wealth in the form of money or property owned by a person or business and human resources of economic value
	assets available for use in the production of further assets