- One that contributes something, such as money, to a cause or fund.
- Medicine. An individual from whom blood, tissue, or an organ is taken for transfusion, implantation, or transplant.
- Chemistry. An atom, molecule, or ion that provides a part to combine with an acceptor, especially an atom that provides two electrons to form a bond with another atom.
- Electronics. An element introduced into a semiconductor with a negative valence greater than that of the pure semiconductor.
Used for transfusion, implantation, or transplant: a donor organ.
[Middle English, from Anglo-Norman donour, from Latin dōnātor, from dōnāre, to give. See donation.]







