<unk>  are extensions to a diagnosis to further clarify a disorder or illness. They allow for a more specific diagnosis. They are used extensively in the Diagnostic & Statistical Manual of Mental Disorders (DSM-5) primarily in the diagnosis of mood disorders.<unk>  are not mutually exclusive and more than one<unk> may be applied on a patient.
Specifier 
Antigen
Pollutant
Immunogen
Endotype
Bioprocess
Chemical nomenclature
Isotype 