/ ˈdəʊnə(r); NAmE ˈdoʊ-/ noun
1.
a person or an organization that makes a gift of money, clothes, food, etc. to a charity, etc. :
international aid donors (= countries which give money, etc. to help other countries)
She is one of the charity's main donors.
2.
a person who gives blood or a part of his or her body to be used by doctors in medical treatment :
a blood donor
The heart transplant will take place as soon as a suitable donor can be found.
donor organs
a donor card (= a card that you carry giving permission for doctors to use parts of your body after your death)
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WORD ORIGIN
Middle English : from Old French doneur , from Latin donator , from donare give.