Radioactivity
Synonyms
Decay, Nuclear
Disintegration, Radioactive
Disintegrations, Radioactive
Nuclear Decay
Radioactive Disintegration
Radioactive Disintegrations
Radioactivities
The spontaneous transformation of a nuclide into one or more different nuclides, accompanied by either the emission of particles from the nucleus, nuclear capture or ejection of orbital electrons, or fission. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)