earpiece vs oratory

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. 

oratory

noun
  • The art of public speaking, especially in a formal, expressive, or forceful manner. 

  • Eloquence; the quality of artistry and persuasiveness in speech or writing. 

  • A Roman Catholic chapel; a building for public or private worship that is not a parish church. 

  • A private chapel or prayer room. 

  • A Catholic church belonging to the Oratory of Saint Philip Neri. 

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