greatgrandchild
A great-grandchild is the child of one's grandchild. This means that a great-grandchild is two generations removed from their great-grandparent. The relationship is established through two generations of descendants. For instance, if someone has a child, and that child has a child, and that child then has a child, the last child is the great-grandchild of the original person.
The term "great-grandchild" is a standard genealogical term used to describe familial relationships. It signifies a