Found 2 items, similar to grandnephew.
English → English (WordNet)
Definition: grandnephew
grandnephew
n : a son of your niece or nephew [syn:
great-nephew]
English → English (gcide)
Definition: Grandnephew
Grandnephew
\Grand“neph”ew\, n.
The grandson of one's brother or sister.
[1913 Webster]