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.
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.
A person who shares a parent; one's brother or sister who one shares a parent with.
A node in a data structure that shares its parent with another node.
The most closely related species, or one of several most closely related species when none can be determined to be more closely related.