darn vs furbish up

darn is a noun but furbish up is not a noun.

Word	Noun	Adjective	Verb	Adverb
darn	Yes	No	Yes	No
furbish up	No	No	Yes	No

As verbs, furbish up is a hypernym of darn; that is, furbish up is a word with a broader meaning than darn:

darn: repair by sewing
furbish up: restore by replacing a part or putting together what is torn or broken

Other hypernyms of darn include bushel, doctor, fix, mend, repair, restore, touch on.

darn (noun)	furbish up (noun)
sewing that repairs a worn or torn hole (especially in a garment)
something of little value

darn (verb)	furbish up (verb)
repair by sewing	restore by replacing a part or putting together what is torn or broken