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ribonucleoside

American  
[rahy-boh-noo-klee-uh-sahyd, -nyoo-] / ˌraɪ boʊˈnu kli əˌsaɪd, -ˈnyu- /

noun

Biochemistry.
  1. a ribonucleotide precursor that contains ribose and a purine or pyrimidine base.


Etymology

Origin of ribonucleoside

First recorded in 1930–35; ribo(nucleic acid) + nucleoside