oldness vs old

oldness and old both are nouns.

Word	Noun	Adjective	Verb	Adverb
oldness	Yes	No	No	No
old	Yes	Yes	No	No

oldness (noun)	old (noun)
the quality of being old; the opposite of newness	past times
the opposite of youngness

oldness (adjective)	old (adjective)
	of long duration; not new
	(used especially of persons) having lived for a relatively long time or attained a specific age
	skilled through long experience
	(used for emphasis) very familiar
	excellent
	just preceding something else in time or order
	belonging to some prior time