A daughter of one’s cousin or cousin-in-law
A daughter of one’s sibling, brother-in-law, or sister-in-law; either the daughter of one's brother ("fraternal niece"), or of one's sister ("sororal niece").
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.