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Medical Dictionary

thoron

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noun tho·ron \ˈthō(ə)r-ˌän, ˈthȯ(ə)r-\

Medical Definition of thoron

  1. :  a heavy radioactive isotope of radon of mass number 220 that is formed as a decay product of thorium, decays by emission of an alpha particle, and has a half-life of less than a minute




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