Definition of eustachian tube
: a bony and cartilaginous tube connecting the middle ear with the nasopharynx and equalizing air pressure on both sides of the tympanic membrane
— called also auditory tube
— see ear illustrationKeep scrolling for more
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Merriam-Webster unabridgedWords at Play
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Time Traveler for eustachian tube
The first known use of eustachian tube was in 1741
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