diesel vs fossil fuel

diesel

noun
  • A fuel derived from petroleum (or other oils) but heavier than gasoline/petrol. Used to power diesel engines which burn this fuel using the heat produced when air is compressed. 

  • Synonym of snakebite and black. 

  • A rider who has an even energy output, without bursts of speed. 

  • A particular cannabis hybrid. 

  • A vehicle powered by a diesel engine. 

verb
  • To ignite a substance by using the heat generated by compression. 

  • For a spark-ignition internal combustion engine to continue running after the electrical current to the spark plugs has been turned off. This occurs when there's enough heat in the combustion chamber to ignite the air and fuel mixture without a spark, the same way that heat and pressure cause ignition in a diesel engine. 

fossil fuel

noun
  • Any fuel derived from hydrocarbon deposits such as coal, petroleum, natural gas and, to some extent, peat; these fuels are non-renewable, and their burning moves carbon from underground into the atmosphere via the greenhouse gas carbon dioxide. 

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