sinus

Definitions

General English

General Science

  • noun an air-filled cavity in the bones of the face and skull, especially one that opens into the nasal passages
  • noun an indentation between petals or the lobes of a leaf

Medical

  • noun a cavity inside the body, including the cavities inside the head behind the cheekbone, forehead and nose
  • noun a tract or passage which develops between an infected place where pus has gathered and the surface of the skin
  • noun a wide venous blood space
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