#fossa__pit  a concavity in a surface (especially an anatomical depression)
  supertype:  concave_shape  bodily_cavity
  subtype:  glenoid_cavity__glenoidcavity__glenoid_fossa__glenoidfossa  the concavity in the head of the scapula that receives the head of the humerus to form the shoulder joint
  subtype:  glenoid_fossa__glenoidfossa__mandibular_fossa  a deep concavity in the temporal bone at the root of the zygomatic arch that receives the condyle of the mandible
  subtype:  pit_of_the_stomach__epigastric_fossa  a slight depression in the midline just below the sternum (where a blow can affect the solar plexus)

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