cautionary tale vs invective

cautionary tale

noun
  • A story, originally told in folklore, to warn its audience of a certain danger. 

invective

noun
  • Something spoken or written, intended to cast shame, disgrace, censure, or reproach on another. 

  • A severe or violent censure or reproach. 

  • A harsh or reproachful accusation. 

  • An expression which inveighs or rails against a person. 

adj
  • Characterized by invection or railing. 

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