co-parent vs old man

co-parent

noun
  • Someone who shares in the parenting of a child or children, such as 

  • A godparent. 

  • A divorced or separated parent who shares custody with the other parent. 

  • A parent in a same-sex couple. 

verb
  • To act as a co-parent; to share custody of a child or children; to share in the responsibility of parenting a child or children. 

old man

noun
  • One's father. 

  • The state of human nature without the spiritual transformation brought about by redemption through Jesus Christ. 

  • Synonym of southernwood 

  • An elderly man. 

  • A husband, or male significant other, irrespective of age. 

  • Used attributively to denote something of exceptional size, strength, age etc. 

  • A unit's commanding officer, or the commander of a naval vessel, irrespective of age. 

  • One's male employer, irrespective of age. 

How often have the words co-parent and old man occurred in a corpus of books? (source: Google Ngram Viewer )