gab vs liquefied petroleum gas

gab

noun
  • One of the open-forked ends of rods controlling reversing in early steam engines. 

  • The mouth or gob. 

  • Idle chatter. 

verb
  • To talk or chatter a lot, usually on trivial subjects. 

liquefied petroleum gas

noun
  • A mixture of propane and butane with traces of some other gases, which is kept in a liquid state at high pressure in metal bottles, and used as a source of gas for cooking, heating and as a fuel in internal combustion engines in vehicles. 

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