a synonym of superannuated is ancient Old- Apex :]
dated, antiquated, outdated, old
Superannuated has the synonyms outdated, outmoded, old-fashioned, or antiquated.
Both are correct.
Synonym means: a word having the same or nearly the same meaning as another in the language. Definition means: the act of defining or making definite, distinct, or clear / the formal statement of the...