Someone you are "friends" with on a website, such as Facebook and don't aknowledge when you see them outside the internets . You talk to eachother, make up inside jokes, and even have deep and meaningful conversations for hours online. However, you mutually don't even grant eachother a simple "Hey" when passing in real live.
"So is Anna going to be at your party this Friday? I saw your wall-to-wall and you guys seem to be pretty close these days."
"Hahah, no way. We're just face-friends. I have no desire to see her in the flesh."