gramma vs grandmother

gramma

noun
  • Something that is written. 

  • The subjects of reading, writing, and arithmetic. 

  • A variety of pumpkin, a cultivar of Cucurbita moschata. 

grandmother

noun
  • A mother of someone's parent. 

  • A female ancestor or progenitor. 

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