radiocarbon dating

American  

noun

1. the determination of the age of objects of organic origin by measurement of the radioactivity of their carbon content.

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radiocarbon dating British  

noun

1. Also called: carbon-14 dating.  a technique for determining the age of organic materials, such as wood, based on their content of the radioisotope ¹⁴ C acquired from the atmosphere when they formed part of a living plant. The ¹⁴ C decays to the nitrogen isotope ¹⁴ N with a half-life of 5730 years. Measurement of the amount of radioactive carbon remaining in the material thus gives an estimate of its age

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radiocarbon dating Scientific  

1. A technique for measuring the age of organic remains based on the rate of decay of carbon 14. Because the ratio of carbon 12 to carbon 14 present in all living organisms is the same, and because the decay rate of carbon 14 is constant, the length of time that has passed since an organism has died can be calculated by comparing the ratio of carbon 12 to carbon 14 in its remains to the known ratio in living organisms.

2. Also called carbon-14 dating

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Closer Look

In the late 1940s, American chemist Willard Libby developed a method for determining when the death of an organism had occurred. He first noted that the cells of all living things contain atoms taken in from the organism's environment, including carbon; all organic compounds contain carbon. Most carbon consists of the isotopes carbon 12 and carbon 13, which are very stable. A very small percentage of carbon, however, consists of the isotope carbon 14, or radiocarbon, which is unstable. Carbon 14 has a half-life of 5,780 years, and is continuously created in Earth's atmosphere through the interaction of nitrogen and gamma rays from outer space. Because atmospheric carbon 14 arises at about the same rate that the atom decays, Earth's levels of carbon 14 have remained fairly constant. Once an organism is dead, however, no new carbon is actively absorbed by its tissues, and its carbon 14 gradually decays. Libby thus reasoned that by measuring carbon 14 levels in the remains of an organism that died long ago, one could estimate the time of its death. This procedure of radiocarbon dating has been widely adopted and is considered accurate enough for practical use to study remains up to 50,000 years old.

Etymology

Origin of radiocarbon dating

First recorded in 1950–55

Example Sentences

To confirm this idea, the team used radiocarbon dating on this core and others collected near Cape Mendocino, where the two fault systems meet.

From Science Daily • May 2, 2026

These included DNA analysis to study genetic relationships, radiocarbon dating to determine the age of the remains, and isotopic measurements to identify where the individuals likely lived before death.

From Science Daily • Apr. 12, 2026

To avoid disturbing the sites further, the team relied on radiocarbon dating of clam shells and deer bones that were originally collected some 50 years ago.

From Science Daily • Nov. 24, 2025

Originally excavated in 1981 from the grounds of St Giles' Cathedral, the remains have undergone new detailed analysis using advanced methods including ancient DNA sequencing, isotopic analysis and radiocarbon dating.

From BBC • Nov. 3, 2025

Archaeologists date food production by radiocarbon dating of carbon-containing materials at the site.

From "Guns, Germs, and Steel: The Fates of Human Societies" by Jared M. Diamond