As a Noun: 1. A pair of speakers inside pads which you wear over your ears in order to listen to a radio, record player, or tape recorder without other people hearing it. English = headphone, headphones, earphone, earphones. 2. A person whose job is to test and measure people's hearing ability. English = audiologist. 3. 4. The study, testing and measurement of people's hearing ability. English = audiology. As a Verb or Adjective: 1. To wear a pair of headphones or earphones.