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radium

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noun, often attributive ra·di·um \ˈrā-dē-əm\

Simple Definition of radium

  • : a radioactive element that is used medically in cancer treatments

Source: Merriam-Webster's Learner's Dictionary

Full Definition of radium

  1. :  an intensely radioactive brilliant white metallic element that resembles barium chemically, occurs in combination in minute quantities in minerals (as pitchblende or carnotite), emits alpha particles and gamma rays to form radon, and is used chiefly in luminous materials and in the treatment of cancer — see element table

Origin and Etymology of radium

New Latin, from Latin radius ray


First Known Use: 1899


RADIUM Defined for Kids

radium

play
noun ra·di·um \ˈrā-dē-əm\

Definition of radium for Students

  1. :  a strongly radioactive element found in very small quantities in various minerals (as pitchblende) and used in the treatment of cancer




Medical Dictionary

radium

play
noun , often attributive ra·di·um \ˈrād-ē-əm\

Medical Definition of radium

  1. :  an intensely radioactive shining white metallic element that resembles barium chemically, that occurs in combination in minute quantities in minerals (as pitchblende or carnotite) principally as the isotope of mass number 226 formed from uranium 238, having a half-life of 1620 years, and emitting alpha particles and gamma rays to form radon, and that is used chiefly in luminous materials and in the treatment of cancer—symbol Ra; see element table




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