Formal term for a person who gives something, especially in legal, financial, or medical contexts. Often used in contrast with 受贈者 (recipient).
Organ donors undergo strict screening.
The donor must sign the contract.
寄付者 is a more general term for a contributor or donor, often used for charitable donations, while 贈与者 is more formal and legal.
Compound of 贈与 (donation, gift) + 者 (person). The word is a straightforward Sino-Japanese formation.