from The American Heritage® Dictionary of the English Language, 4th Edition
- n. Anatomy A slender tube that connects the tympanic cavity with the nasal part of the pharynx and serves to equalize air pressure on either side of the eardrum.
After Bartolomeo Eustachio.(American Heritage® Dictionary of the English Language, Fourth Edition)
In persons in whom from disease or a cold the eustachian tube is permanently or temporarily closed, the sense of hearing is injured; but this may be accounted for by mucus accumulating within the tube, and the consequent exclusion of air.