RichThesaurus
not as young as one used to be
vs
octogenarian
not as young as one used to be
octogenarian
noun
Synonym of eightysomething: a person between 80 and 89 years old.
adj
Of or related to eightysomethings.
How often have the words
not as young as one used to be
and
octogenarian
occurred in a corpus of books?
(source:
Google Ngram Viewer
)