molar activity

in radiochemistry
https://doi.org/10.1351/goldbook.M03974
For a specified
isotope
, the
activity
of the compound divided by the amount of the material in moles: Am=An.
Source:
PAC, 1994, 66, 2513. (Nomenclature for radioanalytical chemistry (IUPAC Recommendations 1994)) on page 2515 [Terms] [Paper]