certified property value 

https://doi.org/10.1351/goldbook.08013
Property value of a reference material, accompanied by statements of associated uncertainty and traceability and identified as a certified property value in the reference material certificate.
Note:
In this definition, "traceability" covers both metrological traceability of a measurement result and examination traceability but not object traceability. Similarly, "uncertainty" covers measurement uncertainty and examination uncertainty.
Source:
PAC, 2021, 93, 997. (Metrological and quality concepts in analytical chemistry (IUPAC Recommendations 2021)) on page 1003 [Terms] [Paper]