commanding officer vs matriarch

commanding officer

noun
  • The officer in command of, and typically having ultimate authority over, a military unit. 

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 commanding officer and matriarch occurred in a corpus of books? (source: Google Ngram Viewer )