radioactive decay

[ rey-dee-oh-ak-tiv di-key ]

noun

, Physics.

1. a radioactive process in which a nucleus undergoes spontaneous transformation into one or more different nuclei and simultaneously emits radiation, loses electrons, or undergoes fission.

radioactive decay

noun

1. 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 todecay Also calleddisintegration

radioactive decay

/ rā′dē-ō-ăk′tĭv /

1. 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 .
2. See also decay

Word History and Origins

Origin of radioactive decay¹

First recorded in 1960–65

Example Sentences

The neutronfest is interspersed with radioactive decays that form new elements.

From Science News

This mineral contains tiny amounts of uranium, which very slowly turns into lead via radioactive decay.

From Singularity Hub 

The team determined that the rocks formed from lava flows 2 billion years ago, but chemical analysis did not yield the concentration of radioactive elements one would expect if radioactive decay were to explain the volcanism.

From Science News

Because radioactive decay occurs in the nucleus of the atom, half-life doesn’t change with environmental conditions, from the hellish heat and crushing pressures deep inside Earth to the frigid realm of the far solar system.

From Science News

The second type, especially helium, forms as a byproduct of radioactive decay, processes that are still happening.

From Popular-Science

The muon is unstable, eventually undergoing a radioactive decay into an electron.

From Project Gutenberg