What are sinuses?
Sinuses are the air chambers in the bone behind your cheeks, eyebrows and jaw. They make mucus, a fluid that cleans bacteria and other particles out of the air you breathe. Tiny hairs called cilia (say: “sill-ee-ah”) sweep mucus out of your sinuses so it can drain out through your nose.
What is sinusitis?
Sinusitis (say: “sine-you-site-iss”) is the name for a condition in which the lining of your sinuses becomes inflamed.
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Written by familydoctor.org editorial staff
Reviewed/Updated: 01/11
Created: 09/00