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thorium

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noun tho·ri·um \ˈthȯr-ē-əm\

Definition of thorium

  1. :  a radioactive metallic element that is obtained especially from monazite and is usually associated with rare earths — see element table



Origin of thorium

New Latin, from Old Norse Thōrr Thor


First Known Use: 1832


Medical Dictionary

thorium

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noun tho·ri·um \ˈthōr-ē-əm, ˈthȯr-\

Medical Definition of thorium

  1. :  a radioactive metallic element that occurs combined in minerals and is usually associated with rare earths—symbol Th; see element table




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