bleep vs chirl

bleep

verb
  • To emit one or more bleeps. 

  • To edit out inappropriate spoken language in a broadcast by replacing offending words with bleeps. 

noun
  • A broad genre of electronic music with goth and industrial influences, as opposed to traditional gothic rock. 

  • A brief high-pitched sound, as from some electronic device. 

  • Something named by an explicit noun in the original, unedited version of the containing sentence. 

chirl

verb
  • To emit a low sound; to warble. 

noun
  • A kind of musical warble. 

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