Search Result for "grandnephew": 
Wordnet 3.0

NOUN (1)

1. a son of your niece or nephew;
[syn: great-nephew, grandnephew]



The Collaborative International Dictionary of English v.0.48:

Grandnephew \Grand"neph"ew\, n.
   The grandson of one's brother or sister.
   [1913 Webster]


WordNet (r) 3.0 (2006):

grandnephew
    n 1: a son of your niece or nephew [syn: great-nephew,
         grandnephew]