half life

of a radionuclide
Synonym: radioactive half life
https://doi.org/10.1351/goldbook.H02717
For a single @R05083@ process, the time required for the activity to decrease to half its value by that process.
Source:
PAC, 1994, 66, 2513. (Nomenclature for radioanalytical chemistry (IUPAC Recommendations 1994)) on page 2520 [Terms] [Paper]