radioactive decay
noun Physics.
Origin of radioactive decay
First recorded in 1960–65
Words nearby radioactive decay
British Dictionary definitions for radioactive decay
radioactive decay
noun
disintegration of a nucleus that occurs spontaneously or as a result of electron capture. One or more different nuclei are formed and usually particles and gamma rays are emitted
Sometimes shortened to: decay Also called: disintegration
Scientific definitions for radioactive decay
radioactive decay
[ rā′dē-ō-ăk′tĭv ]
The spontaneous transformation of an unstable atomic nucleus into a lighter one, in which radiation is released in the form of alpha particles, beta particles, gamma rays, and other particles. The rate of decay of radioactive substances such as carbon 14 or uranium is measured in terms of their half-life. See also decay radioisotope.