Talk about old times (9)
I believe the answer is:
reminisce
'talk about old times' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for reminisce that I've seen before include "Have fond recollections" , "Recount memories" , "Talk about old times - I'm sincere (anag)" , "Recollect past events" , "Think of past events" .)