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Fambush - to be ambushed on facebook. For example when an unwanted person cuts in on a wall conversation, commonly with the result that the unwanted person invites themselves to an event.
Friend 1: "Hey! My main man! Let's meet up at the pub tomorrow for some volcanic lash"

Friend 2: "Mate. That would be literally lolicopter. See you there at 7"

Non-Friend: "Oh wowzarooney! I would love to come for a drink with you guys. I haven't heard from you in ages. I wonder why that is. japes. see you tomorrow at 7"

Friend 1 (aside): "Sheeeeeeeeeeit. We just got propz fambushed"
by Lashley Cole June 11, 2011
Fambush: A word used to describe unexpected visits by family members.
IE: I was fambushed by the in-laws last night.
by JTB11 January 03, 2010
When one suprises a person or significant other by bringing them to family event or residence without prior knowledge of these happenings.
" We are at your moms for July 4th...you just fambushed me, I could have made something"
by UnicornRainbowMarbelyEyes November 08, 2013
When family unexpectedly arrives and you feel ambushed.
"Dude, I came home last night and all my aunts and uncles were there, I totally got fambushed."
by drekos September 05, 2011