chirl vs intonation

chirl

noun
  • A kind of musical warble. 

verb
  • To emit a low sound; to warble. 

intonation

noun
  • A sound made by, or resembling that made by, a musical instrument. 

  • Emotive stress used to increase the power of delivery in speech. 

  • Reciting in a musical prolonged tone; intonating or singing of the opening phrase of a plain-chant, psalm, or canticle by a single voice, as of a priest. 

  • The rise and fall of the voice in speaking. 

  • Singing or playing in good tune or otherwise. 

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