Coin in bank not long ago (8)
I believe the answer is:
recently
'not long ago' is the definition.
(thesaurus)
'coin in bank' is the wordplay.
'coin' becomes 'cent' (cent is a kind of coin).
'in' is an insertion indicator.
'bank' becomes 'rely' (I've seen this before).
'cent' inserted into 'rely' is 'RECENTLY'.
(Other definitions for recently that I've seen before include "Lately" , "Happening not long ago" , "Not so long since" , "Adverb meaning not long ago" , "In the near past" .)