Radioactive decay is the process by which an unstable atomic nucleus loses energy by radiation. A material containing unstable nuclei is considered radioactive. Three of the most common types of decay are alpha decay, beta decay, and gamma decay, all of which involve emitting one or more particles.
the giving off of rays of energy or particles by the breaking apart of atoms of certain elements (as uranium) 2 : the rays or particles that are given off when atoms break apart.
The three most common types of radiation are alpha particles, beta particles, and gamma rays.
Radioactivity is the spontaneous disintegration of heavier unstable nuclei to form lighter stable nuclei with release of energy particles such as alpha particles, beta particles and gamma rays
