alleviation vs quelling

alleviation

noun
  • the act of alleviating; relief or mitigation. 

  • the act of reducing pain or anything else unpleasant; easement 

quelling

noun
  • The act by which something is quelled. 

adj
  • causing something to quell or be quelled 

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