quelling vs quenching

quelling

adj
  • causing something to quell or be quelled 

noun
  • The act by which something is quelled. 

quenching

noun
  • The rapid cooling of a hot metal object, by placing it in a liquid, in order to harden it. 

  • The extinction of any of several physical properties. 

  • A process in which a galaxy loses cold gas, thus strongly suppressing star formation. 

  • The dissipation of energy from light in excess of what can be used for photosynthesis. 

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