exhaust vs liquefied petroleum gas

exhaust

noun
  • exhaust gas. 

  • An exhaust pipe, especially on a motor vehicle. 

  • A system consisting of the parts of an engine through which burned gases or steam are discharged; see also exhaust system. 

  • The steam let out of a cylinder after it has done its work there. 

  • The dirty air let out of a room through a register or pipe provided for the purpose. 

verb
  • To empty by drawing or letting out the contents 

  • To bring out or develop completely 

  • To discuss thoroughly or completely 

  • To subject to the action of various solvents in order to remove all soluble substances or extractives 

  • To draw or let out wholly; to drain off completely (:liquid) 

  • to tire out; to wear out; to cause to be without any energy 

  • To use up; to deplete, drain or expend wholly, or until the supply comes to an end 

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 exhaust and liquefied petroleum gas occurred in a corpus of books? (source: Google Ngram Viewer )