NCI Dictionary of Cancer Terms
The NCI Dictionary of Cancer Terms features 8,535 terms related to cancer and medicine.
We offer a widget that you can add to your website to let users look up cancer-related terms. Get NCI’s Dictionary of Cancer Terms Widget.
- sphenoid sinus
- listen (SFEE-noyd SY-nus)
A type of paranasal sinus (a hollow space in the bones around the nose). There are two large sphenoid sinuses in the sphenoid bone, which is behind the nose between the eyes. The sphenoid sinuses are lined with cells that make mucus to keep the nose from drying out.