RNA

noun

ˌär-(ˌ)en-ˈā How to pronounce RNA (audio)
: any of various nucleic acids that contain ribose and uracil as structural components and are associated with the control of cellular chemical activities compare messenger rna, ribosomal rna, transfer rna

Examples of RNA in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The third iteration, released in 2024, expanded its prediction abilities to interactions among proteins and other molecules, including DNA, RNA and potential drugs. — Mary Randolph, Scientific American, 7 Aug. 2026 Jeff Coller is the Bloomberg distinguished professor of RNA biology and therapeutics at Johns Hopkins University and a co-founder of the Alliance for mRNA Medicines. — Jeff Coller, STAT, 6 Aug. 2026 However, for applications other than vaccines, a cleaner RNA product is necessary to reduce side effects. — Li Li, The Conversation, 6 Aug. 2026 Undeterred, the team simplified things and fed AlphaFold only the DNA, RNA, and Cas9 protein, since the latter is the primary factor determining its sequence specificity. — ArsTechnica, 24 July 2026 See All Example Sentences for RNA

Word History

Etymology

ribonucleic acid

First Known Use

1942, in the meaning defined above

Time Traveler
The first known use of RNA was in 1942

Phrases Containing RNA

Browse Nearby Words

RN
RNA
RNAi
See all Nearby Words

Cite this Entry

“RNA.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/RNA. Accessed 11 Aug. 2026.

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Kids Definition

RNA

noun
ˌär-ˌen-ˈā How to pronounce RNA (audio)
: any of various nucleic acids that are typically found in the cytoplasm of cells, are usually composed of a single chain of nucleotides, differ from DNA in containing ribose as the five-carbon sugar instead of deoxyribose, and that function mostly in protein synthesis

called also ribonucleic acid

compare messenger rna, ribosomal rna, transfer rna

Medical Definition

RNA

noun
ˌär-ˌen-ˈā How to pronounce RNA (audio)
: any of various nucleic acids that contain ribose and uracil as structural components and are associated with the control of cellular chemical activities

called also ribonucleic acid

see messenger rna, ribosomal rna, transfer rna

More from Merriam-Webster on RNA

Britannica.com: Encyclopedia article about RNA

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