great-grandniece-in-law Share definition Flag 1- Great-grandnephew's wife. 2- Spouse's great-grandniece. My great-grandniece-in-law is a good person. great-grandniece-in-law by Gerald128 April 7, 2021 0 0 Get merch Get the great-grandniece-in-law mug. Buy Now — $32.95 See more merch