Savings book (7)
I believe the answer is:
reserve
I believe this is a double definition.
'savings' is the first definition.
(I've seen this before)
'book' is the second definition.
(I've seen this before)
(Other definitions for reserve that I've seen before include "Savings - book" , "Set aside - shyness" , "left on the bench?" , "Twelfth man < 's coolness" , "Keep back - book" .)