paranasal sinus

noun

Medical Definition of paranasal sinus

: any of various sinuses (as the maxillary sinus and frontal sinus) in the bones of the face and head that are lined with mucous membrane derived from and continuous with the lining of the nasal cavity

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“Paranasal sinus.” The Merriam-Webster.com Medical Dictionary, Merriam-Webster Inc., https://www.merriam-webster.com/medical/paranasal%20sinus. Accessed 9 December 2019.

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