Niece
Part of speech: noun
Definition: A daughter of someone's sibling, brother-in-law, or sister-in-law; either or one's brother ("fraternal niece") or of one's sister ("sororal niece").
Aunt
Part of speech: noun
Definition: a sister or sister-in-law of someone's parent(also great-aunt or grandaunt) a person's grandparent's sister or sister-in-law.(usually auntie) a grandmother.an affectionate term for a woman of an older generation than oneself, especially a friend of one's parents, by means of fictive kin.