radioactivity

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

Definition of radioactivity

  1. :  the property possessed by some elements (such as uranium) or isotopes (such as carbon 14) of spontaneously emitting energetic particles (such 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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