noun
radionuclide; radioactive nuclide
Technical term in nuclear physics and radiochemistry. Refers to an atom with an unstable nucleus that undergoes radioactive decay.
放射性核種の半減期は核種によって大きく異なる。
The half-life of a radionuclide varies greatly depending on the nuclide.
環境中の放射性核種の動態を調査している。
We are investigating the behavior of radionuclides in the environment.