SINCE 1828

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eustachian tube

noun, often capitalized E eu·sta·chian tube \ yü-ˈstā-sh(ē-)ən- also -ˈstā-kē-ən- \

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 illustration

See eustachian tube defined for kids

Origin and Etymology of eustachian tube

Bartolommeo Eustachio

NEW! Time Traveler

First Known Use: 1741

in the meaning defined above

See Words from the same year

Medical Dictionary

eustachian tube

noun, often capitalized E

medical 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, pharyngotympanic tube

Illustration of eustachian tube

Learn More about eustachian tube

Britannica.com: Encyclopedia article about eustachian tube

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