casket vs fuel tank

casket

noun
  • A gasket. 

  • An urn. 

  • A little box, e.g. for jewellery. 

  • A coffin. 

verb
  • To put into, or preserve in, a casket. 

fuel tank

noun
  • A container of fuel, especially one inside a vehicle. 

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