A compound of the word PLACEBO, and the first six letters of the word FACEBOOK
1. Pretending to be one way on Facebook, but actually being another. 2. A person who wants to be your friend on FACEBOOK, but in real life will shun you.
Pronounced Fa See Bo
George:I got a friend request from Gennifer, but I didn't accept her because she is such a FLACEBO.
Fred: I hear you! outside of Facebook, she never says a word to me.