frontal sinus

noun

Medical Definition of frontal sinus

: either of two air spaces lined with mucous membrane each of which lies within the frontal bone above one of the orbits

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Dictionary Entries Near frontal sinus

frontal process

frontal sinus

frontal vein

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Cite this Entry

“Frontal sinus.” Merriam-Webster.com Medical Dictionary, Merriam-Webster, https://www.merriam-webster.com/medical/frontal%20sinus. Accessed 2 Aug. 2021.

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