Aida perhaps quiet in old age (5)
I believe the answer is:
opera
'aida' is the definition.
(I've seen this in another clue)
'quiet in old age' is the wordplay.
'quiet' becomes 'p' (music symbol for 'piano', ie soft or quiet).
'in' is an insertion indicator.
'old' becomes 'o' (abbreviation as in OT - Old Testament).
'age' becomes 'era' (both can mean a long time).
'o'+'era'='oera'
'p' inserted within 'oera' is 'OPERA'.
'perhaps' is the link.
(Other definitions for opera that I've seen before include "One at the Met" , "could be soap" , "Carmen, for instance" , "Musical dramatic work" , "Musical 11 across" .)