earpiece \ˈ ̷ ̷ˌ ̷ ̷\noun 1.: a piece (as of a helmet or cap) intended to cover and protect the ear 2.: a part of an instrument (as a stethoscope or hearing aid) to which the ear is applied; especially: earphone 3.: one of the two sidepieces that support eyeglasses by passing over or behind the ears