#blood_group__bloodgroup__blood_type__bloodtype  people whose blood (usually just the red blood cells) has the same antigens
  subtype:  #group_A  #group_B  #group_AB  #group_O  #Rh-positive_blood_type  #Rh-negative_blood_type
  supertype:  #people  (plural) any group of human beings (men or women or children) collectively; "old people"; "there were at least 200 people in the audience"
     supertype:  #group__grouping  any number of entities (members) considered as a unit
        supertype:  pm#collection  something gathering separated things (entities/situations)
           supertype:  pm#divisible_entity__divisibleentity  many classifications under this category are application-dependant
              supertype:  pm#entity  something that can be "involved" in a situation
                 supertype:  pm#thing__something___T__t___3D_or_4D_thing_or_anything_else  any category (type or individual) is instance of this type; any type is also a subtype of this type
              supertype:  pm#divisible_thing__divisiblething
                 supertype:  pm#thing__something___T__t___3D_or_4D_thing_or_anything_else  any category (type or individual) is instance of this type; any type is also a subtype of this type

No statement uses or specializes #blood_group; click here to add one.