dastard vs dingo

dastard

noun
  • A malicious coward; a dishonorable sneak. 

verb
  • To dastardize. 

adj
  • Meanly shrinking from danger, cowardly, dastardly. 

dingo

noun
  • A cowardly or otherwise despicable person. 

  • A wild dog native to Australia (Canis familiaris, Canis familiaris dingo, Canis dingo, or Canis lupus dingo). 

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