From Longman Dictionary of Contemporary Englishearpieceear‧piece /ˈɪəpiːs $ ˈɪr-/ noun [countable] 1 TCRa small piece of equipment that you put into your ear to hear a recording, message etc2 [usually plural]MH one of the two pieces at the side of a pair of glasses that go round your ears3 TCTthe part of a telephone that you listen through
Examples from the Corpus
earpiece• The nurse listened with an earpiece.• One interesting point is that signals for both directions pass through both microphones and both earpieces.• At two minutes past six Holloway pressed his earpiece.• A thin cord leads to Sam's earpiece.• Lift the telephone and hold the microphone next to the telephone earpiece.• Her hand tightened convulsively on the receiver, the earpiece jerked against her face. 