old vs darkened

old is a noun but darkened is not a noun.

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

old (noun)	darkened (noun)
past times

old (adjective)	darkened (adjective)
of long duration; not new	become or made dark by lack of light
(used especially of persons) having lived for a relatively long time or attained a specific age	(of fabrics and paper) grown dark in color over time
skilled through long experience
(used for emphasis) very familiar
excellent
just preceding something else in time or order
belonging to some prior time