oversupply vs furnish

oversupply is a noun but furnish is not a noun.

Word	Noun	Adjective	Verb	Adverb
oversupply	Yes	No	Yes	No
furnish	No	No	Yes	No

As verbs, furnish is a hypernym of oversupply; that is, furnish is a word with a broader meaning than oversupply:

Other hypernyms of oversupply include offer, provide, render, supply.

oversupply (noun)	furnish (noun)
the quality of being so overabundant that prices fall

oversupply (verb)	furnish (verb)
supply with an excess of	give something useful or necessary to
	provide or equip with furniture