diddy vs niggly

diddy

adj
  • very small, tiny 

noun
  • A woman's breast. 

  • A fool, a tit. 

  • A gypsy. 

niggly

adj
  • Trivial, insignificant 

  • Bad-tempered, especially about trivial details. 

  • Pernickety, paying too much attention to small details. 

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