measuredProperty

This term is proposed for full integration into Schema.org, pending implementation feedback and adoption from applications and websites.

Thing > Property > measuredProperty

The measuredProperty of an Observation, either a schema.org property, a property from other RDF-compatible systems e.g. W3C RDF Data Cube, or schema.org extensions such as GS1's.
Values expected to be one of these types
Property
Used on these types
Observation

Source

https://github.com/schemaorg/schemaorg/issues/2291