carbon 12


noun
  1. the isotopic carbon atom that comprises 99 percent of naturally occurring carbon, and that since 1961 has been used as the standard for atomic weight by representing a unit of 12.00000.

Origin of carbon 12

1
First recorded in 1940–45
  • Also car·bon-12 [kahr-buhn-twelv]. /ˈkɑr bənˈtwɛlv/.

Words Nearby carbon 12

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2024

Scientific definitions for carbon 12

carbon 12

  1. A stable isotope of carbon, having six protons and six neutrons in the nucleus. Carbon 12 makes up most naturally occurring carbon.

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