sinus
🇺🇸
/ˈsaɪnəs/
🇬🇧
/ˈsaɪnəs/
A sinus is an air-filled space in the skull that is connected to the nasal passages. It helps with things like breathing and speaking.
I have a headache because of my blocked sinuses.
鼻窦が詰まっているので頭痛がします。