Banknotes or coins (4)
I believe the answer is:
cash
I believe this is a double definition.
'banknotes' is the first definition.
(I've seen this in another clue)
'coins' is the second definition.
(I've seen this before)
(Other definitions for cash that I've seen before include "Ready money" , ""Readies"" , "Brass" , "Hard currency" , "Spondulicks" .)