RNA

noun

ˌär-(ˌ)en-ˈā 

: 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

Only later did more complex molecules like RNA and DNA develop and begin storing information for the purposes of heredity. — Jake Buehler, Quanta Magazine, 11 Nov. 2026

The other was a short segment of RNA that interfered with the creation of an enzyme involved in DHT production. — New Atlas, 11 Nov. 2026

Scientists have found asteroids to be rich in those molecules – for example, the sample of material brought back by the OSIRIS-REx mission from the near-Earth asteroid Bennu contained all the building blocks of RNA. — Keith Cooper, Space.com, 11 Nov. 2026

The others use a technology called small interfering RNA, or siRNA, and may have fewer side effects, such as injection site reactions, Nissen said, than pelacarsen. — Erika Edwards, NBC news, 7 Nov. 2026

Word History

Etymology

ribonucleic acid

First Known Use

1942, in the meaning defined above

Phrases Containing RNA

• messenger RNA
• messenger RNA vaccine
• micro-RNA
• ribosomal RNA
• RNA interference
• RNA polymerase
• RNA virus
• transfer RNA

Kids Definition

RNA

noun

ˌär-ˌen-ˈā 

: 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 

: 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