nunchaku vs tear gas

nunchaku

noun
  • The skill of using this weapon in martial arts. 

  • A weapon originating from Okinawa, Japan, consisting of two sticks joined by a chain or cord. 

tear gas

noun
  • Any lachrymatory, non-lethal chemical compound that causes the eyes to sting and water and/or irritates the respiratory system, mostly used for controlling crowds during riots or as self-defense. 

verb
  • To use tear gas. 

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