Conductive hearing loss is when the normal physical movement (conduction) of sound waves through the external ear canal or the middle ear is blocked or misdirected. Anything that disrupts the passage of sound through the external and middle ear—such as hardened earwax, a hole in the eardrum, a foreign object, abnormal bone growth, swelling, or a tumor—can cause this type of hearing loss.

Conductive hearing loss usually can be reversed by treating the underlying cause.