co-parent vs father

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. 

father

noun
  • A person who plays the role of a father in some way. 

  • The founder of a discipline or science. 

  • A member of a church council. 

  • Something that is the greatest or most significant of its kind. 

  • The archived older version of a file that immediately precedes the current version, and was itself derived from the grandfather. 

  • A term of respectful address for a priest. 

  • Something inanimate that begets. 

  • A male ancestor more remote than a parent; a progenitor; especially, a first ancestor. 

  • A (generally human) male who begets a child. 

  • A term of respectful address for an elderly man. 

verb
  • To act as a father; to support and nurture. 

  • To provide with a father. 

  • To adopt as one's own. 

  • To give rise to. 

  • To be a father to; to sire. 

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