#Eustachian_tube__auditory_tube  either of the paired tubes connecting the middle ears to the nasopharynx; equalizes air pressure on the two sides of the eardrum
  supertype:  salpinx  a tube in the uterus or the ear
  part of:  middle_ear__tympanic_cavity__tympanum  the main cavity of the ear; between the eardrum and the inner ear
     part of:  auditory_apparatus  all of the components of the organ of hearing including the outer and middle and inner ears
        part of:  auditory_system  the sensory system for hearing

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