UK vs refresher

UK and refresher both are nouns.

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

UK (noun)	refresher (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	a course that reviews and updates a topic for those who have not kept abreast of developments
	a drink that refreshes
	a fee (in addition to that marked on the brief) paid to counsel in a case that lasts more than one day