cover-up vs suffocation

cover-up

noun
  • An attempt to conceal or disguise something, especially a wrongdoing or a mistake. 

  • An item of clothing to be worn over a swimsuit while not in the water. 

suffocation

noun
  • A particular act of death or killing by means of asphyxia. 

  • Asphyxia—a condition in which an extreme decrease in the concentration of oxygen in the body accompanied by an increase in the concentration of carbon dioxide leads to loss of consciousness or death. 

  • A child left unattended may die of suffocation. 

How often have the words cover-up and suffocation occurred in a corpus of books? (source: Google Ngram Viewer )