Facebook Flush 

To delete people from your friend list.

I have 2156 "friends" but only actually talk to half of them. It must be time for a Facebook Flush.

Facebook Flush by nrs1970 June 24, 2010

Facebook Flush 

When you realize that you don't really have 5,128 friends, therefore deleting several to thin out the herd.

I hate Farmville, Mafia Wars and don't have any plans on starting a fake fish tank, so I did a Facebook Flush so I don't have to see my wall cluttered with that crap!

Facebook Flush by j4883rwocky November 16, 2010

Facebook Flashing 

The act of randomly popping up on someone's chat therefore,"Flashing" them.

Guy: I was on facebook when this girl randomly pops up on chat

Girl: Oh you mean she "Facebook Flashed" you?

Guy: Yeah. she was totally Facebook flashing!

Facebook Flashing by AbbyVanP September 20, 2010

Facebook Flashmob 

In a collective effort, facebook friends of one person steal and adopt his/her profile picture, and each tag the original owner in their new pic. Then the group then likes and comments on everyone's new profile pic, ensuring a barrage of notifications for the target person. Works much better if the adopted picture is in any way scandalous.

Last night while Matt was out to dinner with his parents, 10 of us got him with a facebook flashmob. His phone must have buzzed non stop with notifications!

Facebook Flashmob by Mister Snarls August 20, 2011