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Wiktionary
presbycusis

alt. (context pathology English) inability of the ears, due to aging, to perceive and focus on high-pitched sounds n. (context pathology English) inability of the ears, due to aging, to perceive and focus on high-pitched sounds

Wikipedia
Presbycusis

Presbycusis (also spelled presbyacusis, from Greek presbys “old” + akousis “hearing”), or age-related hearing loss, is the cumulative effect of aging on hearing. It is a progressive and irreversible bilateral symmetrical age-related sensorineural hearing loss resulting from degeneration of the cochlea or associated structures of the inner ear or auditory nerves. The hearing loss is most marked at higher frequencies. Hearing loss that accumulates with age but is caused by factors other than normal aging ( nosocusis and sociocusis) is not presbycusis, although differentiating the individual effects of multiple causes of hearing loss can be difficult.

Presbycusis is the most common cause of hearing loss, afflicting one out of three persons by age 65, and one out of two by age 75. Presbycusis is the second most common illness next to arthritis in aged people.