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English definition of “sinus”


noun (space in body)    /ˈsaɪ.nəs/
[C] any of the spaces inside the head that are connected to the back of the nose Substances and structures in the body [C] specialized medical a space or passage filled with pus (= a thick yellow liquid ) that flows to the surface of the skin
(Definition of sinus noun (space in body) from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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