Relationship
A Relationship is first-class canonical state connecting two or more identifiable Subjects under a governed relationship type.
Specification-sourced: quoted from the governing specification, pending the applicable specification-owner approvals. The specification controls.
In RSMOne's words
A long relationship between a farm and a mill is more than a bare supplies edge: it has origins, conditions, obligations and a Biography of fulfilled and failed Commitments. That history can affect whether a future Formation is viable.