Similar to radio silence but with facebook. The process by which you appear offline on facebook chat and check what others have written on your wall but do not reply or do anything that may appear in your news feed. This way, nobody else will know that you were on there.
Tim: Dude, I posted the funniest link on your wall and you never replied.
Mark: Oh yeah, I got that when Linda was really pissed off at me and I decided to go to facebook silence so she didn't know I was there.
Steve: I didn't go to the party last night so went to facebook silence so that people didn't know I sat in on facebook all night. This meant I could later give the charade of having had just as cool a night as the party-goers.
Dave: Dude, I haven't replied to that creepy girl who sits behind us in Chemistry on facebook...so now I have to stay at facebook silence whenever I log on so she doesn't know I'm ignoring her and just thinks I'm ignoring facebook.