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do·nor (dōnər)
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n.
1. One that contributes something, such as money, to a cause or fund.
2. Medicine An individual from whom blood, tissue, or an organ is taken for transfusion, implantation, or transplant.
3. 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.
4. Electronics An element introduced into a semiconductor with a negative valence greater than that of the pure semiconductor.
adj.
Medicine Used for transfusion, implantation, or transplant: a donor organ.

[Middle English, from Anglo-Norman donour, from Latin dōnātor, from dōnāre, to give; see DONATION.]

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2016 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 

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