Foot the bill for cure (5)
I believe the answer is:
treat
This clue is a double definition.
'foot the bill' is the first definition.
(I've seen this in another clue)
'cure' is the second definition.
(I've seen this before)
'for' acts as a link.
(Other definitions for treat that I've seen before include "Unexpected surprise" , "Apply remedies" , "Special delight; handle" , "Tend" , "Stand a drink" .)