peril vs unlikelihood

peril

noun
  • A situation of serious and immediate danger. 

  • An event which causes a loss, or the risk of a specific such event. 

  • Something that causes, contains, or presents danger. 

verb
  • To cause to be in danger; to imperil; to risk. 

unlikelihood

noun
  • Absence of likelihood; the state of being unlikely or improbable; improbability. 

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