(medicine) Deafness due to an abnormality of the sense organs or of the nerves involved in hearing.
Impaired hearing caused by pathologic conditions in the auditory nerve or the hair cells of the organ of Corti in the inner ear (for example, high-tone deafness, which comes with age; damage to the organ of Corti by noise; or a tumor of an auditory nerve). Hearing aids are usually of little benefit.