: a pentose C5H10O5 found especially in the dextrorotatory form as a component of many nucleosides (such as adenosine and guanosine) especially in RNA
Examples of ribose in a Sentence
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For life on Earth, the sugars deoxyribose – which the researchers did not detect – and ribose are key building blocks of DNA and RNA, respectively.
—
Eric Lagatta, USA Today, 4 Dec. 2025
Analyzing pristine fragments of the asteroid delivered to Earth by NASA's OSIRIS-REx spacecraft in 2023, a team led by Yoshihiro Furukawa of Tohoku University in Japan found ribose, a crucial building block of RNA, and glucose, an energy-rich sugar used by nearly all life on Earth.
—Sharmila Kuthunur, Space.com, 3 Dec. 2025
Other names commonly used for ribose include ribose sugar and simply ribose.
—Lauren Manaker Ms, Rdn, Health, 19 July 2024
Murchison also contained nucleobases, the building blocks of genetic molecules such as RNA, and in November 2019, researchers found a major component of RNA’s backbone: the sugar molecule ribose.
—Joshua Sokol, Science | AAAS, 13 Aug. 2020
In November 2019, an international team of scientists discovered meteorites carrying the organic sugar ribose, which is essential for the formation of RNA.
—Brad King, WSJ, 7 Feb. 2020
Scientists continue to theorize about the conditions that fostered the birth of life on Earth, and ribose is a key piece of evidence.
—Caroline Delbert, Popular Mechanics, 19 Nov. 2019
For example, all living things only use the right-handed form of the sugar ribose to form the backbone of DNA, giving it that the signature twist.
—Nathaniel Scharping, Discover Magazine, 14 June 2016
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Eric Lagatta, USA Today, 4 Dec. 2025
Analyzing pristine fragments of the asteroid delivered to Earth by NASA's OSIRIS-REx spacecraft in 2023, a team led by Yoshihiro Furukawa of Tohoku University in Japan found ribose, a crucial building block of RNA, and glucose, an energy-rich sugar used by nearly all life on Earth.
—Sharmila Kuthunur, Space.com, 3 Dec. 2025
Other names commonly used for ribose include ribose sugar and simply ribose.
—Lauren Manaker Ms, Rdn, Health, 19 July 2024
Murchison also contained nucleobases, the building blocks of genetic molecules such as RNA, and in November 2019, researchers found a major component of RNA’s backbone: the sugar molecule ribose.
—Joshua Sokol, Science | AAAS, 13 Aug. 2020
In November 2019, an international team of scientists discovered meteorites carrying the organic sugar ribose, which is essential for the formation of RNA.
—Brad King, WSJ, 7 Feb. 2020
Scientists continue to theorize about the conditions that fostered the birth of life on Earth, and ribose is a key piece of evidence.
—Caroline Delbert, Popular Mechanics, 19 Nov. 2019
For example, all living things only use the right-handed form of the sugar ribose to form the backbone of DNA, giving it that the signature twist.
—Nathaniel Scharping, Discover Magazine, 14 June 2016
Cite this Entry
“Ribose.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ribose. Accessed 15 Dec. 2025.
Copy CitationKids Definition
ribose
noun
ri·bose
ˈrī-ˌbōs 
: a sugar that has five carbon atoms and five oxygen atoms in each molecule and is part of RNA compare deoxyribose
Medical Definition
ribose
noun
ri·bose
ˈrī-ˌbōs, -ˌbōz
: a pentose C5H10O5 found especially in the levorotatory D-form as a constituent of a number of nucleosides (as adenosine, cytidine, and guanosine) especially in RNA
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