say it: DOH-nur
donor is a noun meaning "person who makes a gift of property". It carries 2 recorded senses.
person who makes a gift of property
(medicine) someone who gives blood or tissue or an organ to be used in another person (the host)
medicine
Forms marked · are formed by the regular rule rather than recorded in the source data. English keeps a few hundred irregulars and the rest follow the pattern, so the rule is right far more often than not — but it is a rule, and the mark says so.
Definitions, synonyms and semantic relations for donor come from Princeton University’s WordNet. The pronunciation comes from the CMU Pronouncing Dictionary. Commonness is measured against a corpus of everyday English. Full sources and licences.