gelatin vs waternut

gelatin

noun
  • An edible jelly made from this material. 

  • A thin, translucent membrane used as a filter for photography or for theatrical lighting effects. 

  • A protein derived through partial hydrolysis of the collagen extracted from animal skin, bones, cartilage, ligaments, etc. 

waternut

noun
  • Synonym of jelly coconut 

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