#sinus__sinu  any of various air-filled cavities especially in the bones of the skull
  supertype:  bodily_cavity__cavity__cavum  (anatomy) a natural hollow or sinus within the body
  subtype:  ethmoid_sinus__ethmoidsinu__ethmoidal_sinus__ethmoidalsinu__sinus_ethmoidales__sinusethmoidale  a sinus of the meatuses of the nasal cavity (behind the bridge of the nose)
  subtype:  frontal_sinus__frontalsinu  one of a pair of cavities in the frontal bone
  subtype:  maxillary_sinus__maxillarysinu  one of a pair of sinuses forming a cavity in the maxilla
  subtype:  paranasal_sinus__paranasalsinu__sinus_paranasales__sinusparanasale__nasal_sinus__nasalsinu  any of the paired sinuses in the bones of the face adjacent to the nasal cavity that are lined with mucous membrane that is continuous with lining of the nasal cavities

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