nu·​cle·​o·​side | \ ˈnü-klē-ə-ˌsīd How to pronounce nucleoside (audio) , ˈnyü- \

Definition of nucleoside

: a compound (such as guanosine or adenosine) that consists of a purine or pyrimidine base combined with deoxyribose or ribose and is found especially in DNA or RNA

Examples of nucleoside in a Sentence

Recent Examples on the Web But academic researchers found modifying a small part of mRNA called a nucleoside could result in its slipping past the immune system. Juliet Chung, WSJ, "The Millionaire Who Gave Moderna a Shot," 2 Oct. 2020 These ring-like nitrogen molecules were known to be a type of nucleoside, the broad term for the structural bases of DNA. Patrick Adams, National Geographic, "Meet the woman who gave the world antiviral drugs," 31 Aug. 2020 The first nucleoside analogues were approved for medicinal use in the 1950s. Katherine Seley-radtke, The Conversation, "Remdesivir explained – what makes this drug work against viruses?," 6 May 2020 In their newest paper, published in the same journal, the researchers showed that TAP and ribose easily bond when mixed in water, creating molecules known as nucleosides. Quanta Magazine, "Chemists Seek Possible Precursor to RNA," 5 Feb. 2014 In a group of nine patients with a disease similar to Charlie’s, one was able to breathe without a ventilator after being treated with nucleosides to improve muscle function, the doctor said. Joanna Sugden, WSJ, "Charlie Gard Has Chance of Improvement With Therapy, U.S. Doctor Tells Court," 13 July 2017 His parents want to take him to the U.S. for nucleoside therapy. Erin Hill,, "Parents of Terminally Ill Baby Charlie Gard Storm Out of Court After Disagreement with Judge," 13 July 2017 With that, doctors concluded that nucleoside therapy would only prolong the child’s suffering. Dan Bilefsky And Sewell Chan, New York Times, "For Parents of U.K. Infant, Trump’s Tweet Is Latest Twist in an Agonizing Journey," 4 July 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'nucleoside.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of nucleoside

1911, in the meaning defined above

History and Etymology for nucleoside

International Scientific Vocabulary nucle- + -ose entry 2 + -ide

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Time Traveler for nucleoside

Time Traveler

The first known use of nucleoside was in 1911

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Cite this Entry

“Nucleoside.” Dictionary, Merriam-Webster, Accessed 4 Mar. 2021.

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More Definitions for nucleoside


nu·​cle·​o·​side | \ ˈn(y)ü-klē-ə-ˌsīd How to pronounce nucleoside (audio) \

Medical Definition of nucleoside

: a compound (as guanosine or adenosine) that consists of a purine or pyrimidine base combined with deoxyribose or ribose and is found especially in DNA or RNA — compare nucleotide

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