refurbishment vs melioration

refurbishment and melioration both are nouns.

Word	Noun	Adjective	Verb	Adverb
refurbishment	Yes	No	No	No
melioration	Yes	No	No	No

As nouns, melioration is a hypernym of refurbishment; that is, melioration is a word with a broader meaning than refurbishment:

Other hypernyms of refurbishment include improvement.

refurbishment (noun)	melioration (noun)
the state of being restored to its former good condition	the act of relieving ills and changing for the better
	the linguistic process in which over a period of time a word grows more positive in connotation or more elevated in meaning
	a condition superior to an earlier condition