1. Either of the paired tubes connecting the middle ears to the nasopharynx; equalizes air pressure on the two sides of the eardrum
   "The Eustachian tube helped relieve the pressure during the flight";
   - auditory tube

Derived forms: Eustachian tubes

Type of: salpinx

Part of: middle ear, tympanic cavity, tympanum

Encyclopedia: Eustachian tube