The acronym for "What a Freggin' Noob." Used to put someone who has just embarrassed themselves into a further state of embarrassment. Used when only talking about one person. Also See plural Wabofn
Person 1: Dude! Look at this video I found on youtube.
Person 2: Oh man! That was awesome, he totally got owned!
Person 1: Yeah, I know. Wafn.