an acronym for "Grandparent on Facebook." This usually describes but is not limited to grandparents, aunts, uncles, parents, or any other older family member that does not know how to properly use Facebook. This also includes nosey family members and grandparents who think everything on their news feed is aimed directly at them.
"My grandma is always commenting on everything I put on Facebook. It's so embarrassing. She's commenting on my friend's wall too, she doesn't even know them!"
"Looks like you have a goffer problem man. Unfriend her ASAP."