a granddaughter of one's nephew or niece.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
How to use great-grandniece in a sentence
A few days ago a great-grandniece was sent to me, a child under ten years old, that has no other relative.Laboulaye's Fairy Book | Various
Perhaps I could persuade them that the great-grandniece of Cassius Cato would be a deserving object of their consideration.Kit of Greenacre Farm | Izola Forrester
He could not offer to do so till he came back from his great-grandniece Constance's wedding at Cowcester.A Likely Story | William De Morgan