mamaw vs matriarch

mamaw

noun
  • One's grandmother, especially one's maternal grandmother. 

  • One's mother. 

matriarch

noun
  • A female leader of a family, a tribe or an ethnic or religious group. 

  • A female founder of a political or religious movement, an organization or an enterprise. 

  • The dominant female in a family group of elephants 

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