grand-niece       
noun [ C ] (also grandniece, grand nieces) uk/ˈɡrændˌniːs/ us/ˈɡrændˌniːs/
 侄孙女(自己兄弟的儿女的女儿);外甥孙女 (自己姐妹的儿女的女儿)
the daughter of your nephew (= the son of your brother or sister) or niece (= the daughter of your brother or sister)
  The biography was written by his grand-niece. 这本传记是他侄孙女写的。| 这本传记是他外甥孙女写的。 
 An elderly actor has his young grandniece come to stay. 一位年长的演员让他年幼的侄孙女来住。| 一位年长的演员让他年幼的外甥孙女来住。 
 Synonym: great-niece
 - More examples
 - He is haunted by the disappearance of his favourite grand-niece 30 years earlier.
 - His wife was a grand-niece of the Queen Mother.
 - He was originally my four-year old grand niece’s cat.