grandchild vs pa

grandchild

noun
  • A child of someone's child. 

pa

noun
  • Father, papa. 

  • Grandpa, grandfather. 

  • Any Maori village or settlement; a kainga. 

  • A fortified Maori settlement, especially of pre-European times. 

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