obsolete vs superannuated

obsolete and superannuated both are adjectives.

Word	Noun	Adjective	Verb	Adverb
obsolete	No	Yes	No	No
superannuated	No	Yes	No	No

As adjectives, obsolete and superannuated are synonyms defined as:

Other synonyms of obsolete include out-of-date, outdated.

obsolete (adjective)	superannuated (adjective)
no longer in use	old; no longer valid or fashionable
old; no longer valid or fashionable	too old to be useful