The old unit of money in Spain (6)
I believe the answer is:
peseta
'the old unit of money in spain' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for peseta that I've seen before include "Old bread" , "Coin from the sea pet" , "Out of date bread" , "Old unit of money in Spain" , "Get ready once for Spain" .)