a relation between an independent continuant (the bearer) and a role, in which the role specifically depends on the bearer for its existence
A bearer can have many roles, and its roles can exist for different periods of time, but none of its roles can exist when the bearer does not exist. A role need not be realized at all the times that the role exists.
example of usage
this person has role this investigator role (more colloquially: this person has this role of investigator)