State Descriptor - Any combination list of parameterical quantities, classification types, and other  descriptors [parametric representations (tensors, vectors, scalars , equations, and/or words)] which conveniently describe the state of an object or system. In theory, the descriptor could be infinite, but is limited in practice by the things that are determined to be of practical importance.

• For a machine, the nominal state descriptor includes the user selectable machine settings, but the actual state descriptor also includes geometric errors, dynamic errors, uncontrolled external effects (such as ambient temperature),   etc. 

• For example, an object which has a mass of 10 kg and at an average temperature of 35 degrees Celsius may be described with the state descriptor (10 kg, 35 deg C) or just (10,35) if the state descriptor basis has been defined. See also machine state.