piff vs prat

piff

noun
  • Piffle; nonsense; rubbish. 

adj
  • good or attractive. 

verb
  • To throw something vigorously. 

intj
  • An exclamation of annoyance or contempt; pish; pshaw. 

prat

noun
  • A fool. 

  • A cunning or mischievous trick; a prank, a joke. 

  • The female genitals. 

  • A buttock, or the buttocks; a person's bottom. 

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