nucleoside

noun

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

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These carried the building blocks essential to living things: amino acids, lipids, nucleosides, and sugars. — Jocelyn Solis-Moreira, Popular Science, 25 May 2023 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, 2 Oct. 2020

Word History

Etymology

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

First Known Use

1911, in the meaning defined above

Time Traveler
The first known use of nucleoside was in 1911

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“Nucleoside.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/nucleoside. Accessed 17 Mar. 2025.

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Medical Definition

nucleoside

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

More from Merriam-Webster on nucleoside

Britannica.com: Encyclopedia article about nucleoside

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