Skip to definition.
Get the FREE one-click dictionary software for Windows or the iPhone/iPad and Android apps

Noun: sinus  sI-nus
  1. An abnormal passage leading from a suppurating cavity to the body surface
    - fistula
  2. Any of various air-filled cavities especially in the bones of the skull
  3. A wide channel containing blood; does not have the coating of an ordinary blood vessel
    - venous sinus

Derived forms: sinuses

Type of: bodily cavity, canal, cavity, cavum, channel, duct, epithelial duct, passage, passageway

Encyclopedia: Sinus