Giving willingly (7)
I believe the answer is:
leaving
'giving' is the definition.
(leaving is a kind of giving)
I can't explain the remainder of the clue.
Can you help me to learn more?
(Other definitions for leaving that I've seen before include "Going away" , "Departure" , "Abandoning" , "Bequeathing (in will)" , "Departing" .)