Great-niece is typically used in family relationships to denote the daughter of one's niece or nephew. However, there are several synonyms for the term that can be used interchangeably depending on the context and preference. Some of the synonyms for great-niece include grandniece, niece once removed, and grandniece once removed. In certain cultures, the term "niece-in-law" or "niece by marriage" is used to refer to a great-niece. While these terms are not as commonly used, they can be used alongside great-niece to refer to the same familial relationship. Ultimately, the choice of synonym depends on the preference and cultural background of the speaker or writer.