ribosome

noun

ri·​bo·​some ˈrī-bə-ˌsōm How to pronounce ribosome (audio)
: any of the RNA-rich cytoplasmic granules that are sites of protein synthesis see cell illustration
ribosomal
ˌrī-bə-ˈsō-məl How to pronounce ribosome (audio)
adjective

Examples of ribosome 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 proteins made by the ribosome then go off to do their jobs in making and sustaining the organism. — Philip Ball, Quanta Magazine, 18 June 2026 To do that, the researchers decided to remove isoleucine from all of the proteins in the small subunit of the ribosome. — ArsTechnica, 30 Apr. 2026 For Glass, an obvious red line is for scientists to refrain from making a mirror ribosome, a biological machine found in a cell’s cytoplasm that makes proteins. — Katie Hunt, CNN Money, 17 Oct. 2025 This helical strand of molecules allows for information contained in DNA in the nucleus of cells to be delivered to ribosomes where protein synthesis can occur. — Joshua P. Cohen, Forbes.com, 2 Sep. 2025 See All Example Sentences for ribosome

Word History

First Known Use

1958, in the meaning defined above

Time Traveler
The first known use of ribosome was in 1958

Rhymes for ribosome

See All Rhymes for ribosome

Browse Nearby Words

ribosomal RNA
ribosome
ribosyl
See all Nearby Words

Cite this Entry

“Ribosome.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ribosome. Accessed 7 Jul. 2026.

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Kids Definition

ribosome

noun
ri·​bo·​some ˈrī-bə-ˌsōm How to pronounce ribosome (audio)
: one of numerous small RNA-containing particles in a cell that are sites of protein synthesis

Medical Definition

ribosome

noun
ri·​bo·​some ˈrī-bə-ˌsōm How to pronounce ribosome (audio)
: any of the RNA- and protein-rich cytoplasmic granules that are sites of protein synthesis
ribosomal
ˌrī-bə-ˈsō-məl How to pronounce ribosome (audio)
adjective

More from Merriam-Webster on ribosome

Britannica.com: Encyclopedia article about ribosome

Last Updated: - Updated example sentences
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