When you write something on a friends facebook wall and then the next day you meet them in the hallway, both of you knowing about the said wall post, resulting in an awkward I know you know kinda thing. Because nobody says oh hey I wrote on your wall!
facebook taboo:

1: Waddappp dude!

2: Yoooo buddyyyyy *oh shit he knows I wrote on his wall*
by iflgk November 4, 2009
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