Contributor, giver (5)
I believe the answer is:
donor
I believe this is a double definition.
'contributor' is the first definition.
(I've seen this before)
'giver' is the second definition.
(I know that giver can be written as donor)
(Other definitions for donor that I've seen before include "Organ giver?" , "One giving something" , "Someone providing" , "Charitable giver" , "One who gives, maybe blood" .)