uniformly labelled

https://doi.org/10.1351/goldbook.U06556
A @S05556@ compound where all atoms of a particular element are labelled in the same isotopic ratio.
Source:
PAC, 1981, 53, 1887. (Nomenclature of inorganic chemistry: II.1 - Isotopically modified compounds) on page 1895 [Terms] [Paper]