understatement vs whopper

understatement

noun
  • A figure of speech whereby something is made to seem smaller or less important than it actually is, either through phrasing or lack of emphasis, often for ironic effect. 

  • An incomplete disclosure that intentionally withholds relevant information. 

  • An instance of such phrasing or lack of emphasis. 

whopper

noun
  • Something remarkably large. 

  • An outrageous or blatant lie. 

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