kiasi vs poltroon

kiasi

adj
  • Unwilling to take a chance for fear that something bad or unfavourable will happen; cowardly. 

noun
  • A kiasi person. 

poltroon

adj
  • Cowardly. 

noun
  • An ignoble or total coward; a dastard; a mean-spirited wretch. 

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