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1.
1. A heavily accented pronunciation of Facebook from no particular country, but still notable by it's difference from the standard English pronunciation.
2. A standard, shortened response to anything that could be found or researched on Facebook.
3. A nonsensical self-reference to the term Fassbük itself that actually means nothing at all. Often used to avoid discussion altogether.
4. A greeting among Facebook users.
5. A variation on the term Fassbook.

Proper spelling includes the double-dots over the letter "U" - "Fassbük", but not necessary.
Also, the act of using "Fassbük" or Facebook-related activities is referred to as "Fassbüken".
1. "We should stay in touch... get at me on Fassbük!", "Ya for sure am checking der Fassbük!"
2. "All that drama JUST happened! How'd you find out already?" "Fassbük."
3. "Haven't seen you for a minute! What you been up to?" "Fassbük." "What does that even mean?" "Fassbük." "I didn't ask you..." "Fassbük." "AW FORGET IT!!"
4. "YO! What's up, my dude!" "Fassbük!!!" "FASSBÜK!!!!!"
5. "Man dat gyal always deh pon Fassbük."
by BaddaDanU April 04, 2011