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noun

sinus

SEYE-nuhs
noun
1
One of the air-filled cavities in the skull, especially around the nose, that connect to the nasal passages.
"Her sinus was blocked from the cold."
"He suffers from sinus pain every spring."

How to Use Sinus

Learner’s notes

In plain EnglishOne of the hollow spaces in your skull around the nose, often mentioned when they get blocked or infected.

Common pairings
sinus infection sinus pressure blocked sinus

Word Forms

sinuses plural

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Her _____ was blocked from the cold.

Etymology

A learned borrowing from Latin sinus, meaning "a curve, fold, or hollow."

Rhymes for sinus

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Definitions: FreeDict original editorial