ba vs ba'

ba

noun
  • A being's soul or personality, represented as a bird-headed figure, which survives after death but must be sustained with offerings of food. 

  • Father, baba. 

  • A medieval football game played in parts of Scotland around Christmas and New Year. 

ba'

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