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sinus
1 ENTRIES FOUND:
sinus
(noun)
sinus
/
ˈ
saɪnəs/
noun
plural
sinuses
sinus
/
ˈ
saɪnəs/
noun
plural
sinuses
Britannica Dictionary definition of SINUS
[
count
]
:
any of several spaces in the skull that connect with the nostrils
—
usually plural
My
sinuses
are blocked. [=they are filled with mucus that will not drain properly]
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—
often used before another noun
a
sinus
infection/problem
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