earpiece vs headset

earpiece

noun
  • A speaker placed inside or held near to the ear. 

  • The arm on a pair of glasses that hooks over the ear to hold them in place. 

  • A receiver of a telephone to hold near to one's ear. 

headset

noun
  • A pair of headphones or earphones, or a singular headphone or earphone, typically with an attached microphone. 

  • On a bicycle, the system of bearings that connects the fork to the frame. 

  • Any electronic device worn on the head. 

How often have the words earpiece and headset occurred in a corpus of books? (source: Google Ngram Viewer )