Person giving blood (5)
I believe the answer is:
donor
(Other definitions for donor that I've seen before include "patron" , "Subscriber" , "Maker of gift" , "Charitable giver" , "A giver, perhaps of blood" .)
I believe the answer is:
donor
(Other definitions for donor that I've seen before include "patron" , "Subscriber" , "Maker of gift" , "Charitable giver" , "A giver, perhaps of blood" .)