ri·​bose ˈrī-ˌbōs How to pronounce ribose (audio)
: 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

Recent Examples on the Web 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 The malleable compound contains borate, a substance that seemed to protect organic compounds like ribose from going the way of caramelized sugar. Steve Nadis, Discover Magazine, 8 May 2014 Luckily, Benner’s team made a breakthrough in 2013, discovering that a catalyst called molybdate — a form of molybdenum that includes oxygen — can reconfigure the other sugar’s atoms to convert it into ribose. Steve Nadis, Discover Magazine, 8 May 2014 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 The researchers found sugars like arabinose and xylose -- but the most significant finding was ribose. Jessie Yeung, CNN, 21 Nov. 2019 The discovery of ribose also suggests that RNA evolved before DNA, giving scientists a clearer picture of how life may have formed. Jessie Yeung, CNN, 21 Nov. 2019 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'ribose.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


International Scientific Vocabulary, from ribonic acid an acid C5H10O6 obtained by oxidation of ribose

First Known Use

1892, in the meaning defined above

Time Traveler
The first known use of ribose was in 1892

Dictionary Entries Near ribose

Cite this Entry

“Ribose.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ribose. Accessed 1 Mar. 2024.

Kids Definition


ri·​bose ˈrī-ˌbōs How to pronounce ribose (audio)
: a sugar that has five carbon atoms and five oxygen atoms in each molecule and is part of RNA compare deoxyribose

Medical Definition


: 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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