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1.
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.
by nrs1970 June 21, 2010
 
2.
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!
by j4883rwocky November 13, 2010