An<unk>  is a subtype of a health condition, which is defined by a distinct functional or pathobiological mechanism. This is distinct from a phenotype, which is any observable characteristic or trait of a disease, such as development, biochemical or physiological properties without any implication of a mechanism. It is envisaged that patients with a specific<unk>  present themselves within phenotypic clusters of diseases. One example is asthma, which is considered to be a syndrome, consisting of a series of<unk> s. This is related to the concept of disease entity.
Endotype
Isotype 
Serotype
Strain 
Locus
Clone 
Phenotype 
Killing Season