audiphone
/ˈɔːdɪˌfəʊn/a type of hearing aid consisting of a diaphragm that, when placed against the upper teeth, conveys sound vibrations to the inner ear 助听器
noun [专属名词] （美）助听器（等于 dentiphone）
The doctor recommended an audiphone for the elderly gentleman who was struggling to hear conversations. 医生为这位听力困难的老年绅士推荐了一款助听器。
