carbon 13

noun

: an isotope of carbon of mass number 13 that constitutes about ¹/₇₀ of natural carbon and is used as a tracer especially in spectroscopy utilizing nuclear magnetic resonance

Examples of carbon 13 in a Sentence

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Measuring the extent to which multiple carbon 13 atoms (a rare, stable form of carbon with an extra neutron) replace carbon 12 (the most common form of carbon) in a particular molecule, for instance, can tell researchers about the temperature when the compound formed. — Clara Moskowitz, Scientific American, 15 June 2023 These isotopes, carbon 13 and oxygen 18, bond to each other more when the temperature is cooler, a handy relationship that geophysicists have been using to study Earth's past climate in the geological record. — Veronique Greenwood, Discover Magazine, 24 June 2011

Word History

First Known Use

1936, in the meaning defined above

Time Traveler
The first known use of carbon 13 was in 1936

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“Carbon 13.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/carbon%2013. Accessed 22 Mar. 2025.

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