WordNet sense 1 (discharged as too old for use or work; especially with a pension):

retired

WordNet sense 2 (too old to be useful):

overage, overaged, over-the-hill, overage

WordNet sense 3 ((used especially of persons) having lived for a relatively long time or attained a specific age):

old

WordNet sense 4 (old; no longer in use or valid or fashionable):

obsolete, out-of-date, outdated

WordNet sense 5 (not current or belonging to the present time):

noncurrent