Consume; shell out (6)
I believe the answer is:
expend
This clue is a double definition.
'consume' is the first definition.
(I've seen this in another clue)
'shell out' is the second definition.
(I've seen this in another clue)
(Other definitions for expend that I've seen before include "Use up (a resource)" , "Pay out money" , "Use up (resources)" , "Consume" , "Spend or use up" .)