chirl vs piping

chirl

noun
  • A kind of musical warble. 

verb
  • To emit a low sound; to warble. 

piping

noun
  • The sound of musical pipes. 

  • An act of making music or noise with pipes. 

  • A system of pipes that compose a structure; pipework. 

  • The process of an animal just beginning to break out of its egg; precedes hatching. 

  • An ornamentation on the edges of a garment; a small cord covered with cloth. 

  • Icing extruded from a piping bag. 

  • propagation by cuttings 

  • A piece cut off to be set or planted; a cutting. 

adj
  • High-pitched. 

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