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 system for copying parts of the genome into RNA for protein production comes from a virus called T7. — ArsTechnica, 2 July 2026 There’s a lot of evidence that RNA molecules in different ways are a very important part of that story. — Quanta Magazine, 11 June 2026 At least one case study indicates that viral RNA can persist in human bodily fluids for years after infection. — Adam Kovac, Scientific American, 15 May 2026 But the field has struggled to figure out a means of delivering RNA-muting molecules into organs and tissues beyond the liver, which has limited their reach. — Elaine Chen, STAT, 9 June 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 7 Jul. 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

Last Updated: - Updated example sentences
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