recitative vs serenade

recitative

noun
  • dialogue, in an opera etc, that, rather than being sung as an aria, is reproduced with the rhythms of normal speech, often with simple musical accompaniment or harpsichord continuo, serving to expound the plot 

adj
  • of a recital 

serenade

noun
  • An instrumental composition in several movements. 

  • A love song that is sung directly to one's love interest, especially one performed below the window of a loved one in the evening. 

verb
  • To sing or play a serenade for (someone). 

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