#headache__concern__worry__vexation  something or someone that causes anxiety; a source of unhappiness; "New York traffic is a constant concern"; "it's a major worry"
  subtype:  #bugaboo  #onus  #business.headache
  supertype:  #negative_stimulus  a stimulus with undesirable consequences
     supertype:  #stimulus__stimulation__stimulant__input  any stimulating information or event; acts to arouse action
        supertype:  #information  knowledge acquired through study or experience or instruction
           supertype:  pm#thing_that_can_be_seen_as_a_relation  usable as relation type
              supertype:  pm#thing_playing_some_role  category to classify things according to roles/viewpoints; classification under this category is application-dependant
                 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 #headache; click here to add one.