radioactivity

play
noun ra·dio·ac·tiv·i·ty \-ak-ˈti-və-tē\

Definition of radioactivity

  1. :  the property possessed by some elements (as uranium) or isotopes (as carbon 14) of spontaneously emitting energetic particles (as electrons or alpha particles) by the disintegration of their atomic nuclei; also :  the rays emitted

Origin and Etymology of radioactivity

International Scientific Vocabulary


First Known Use: 1899


RADIOACTIVITY Defined for Kids

radioactivity

play
noun ra·dio·ac·tiv·i·ty \ˌrā-dē-ō-ak-ˈti-və-tē\

Definition of radioactivity for Students

  1. 1 :  the giving off of rays of energy or particles by the breaking apart of atoms of certain elements (as uranium)

  2. 2 :  the rays or particles that are given off when atoms break apart


Medical Dictionary

radioactivity

play
noun ra·dio·ac·tiv·i·ty \-ak-ˈtiv-ət-ē\

Medical Definition of radioactivity

plural

radioactivities

  1. :  the property possessed by some elements (as uranium) or isotopes (as carbon 14) of spontaneously emitting energetic particles (as electrons or alpha particles) by the disintegration of their atomic nuclei



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