snicker vs split one’s sides

snicker

noun
  • A stifled or broken laugh. 

  • A player who snicks the ball. 

verb
  • To emit a snicker, a stifled or broken laugh. 

  • To whinny. 

  • To utter through a laugh of this kind. 

split one’s sides

How often have the words snicker and split one’s sides occurred in a corpus of books? (source: Google Ngram Viewer )