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1.
fucking fantastic
BOB: Dude that weed was fucknastic!

ROB: That wasn't weed dumb fuck it was oregano..

BOB: Oh :'~(
by Regan Lee:D July 12, 2009
 
2.
The practise of performing overly elaborate gymnastic or sometimes acrobatic sexual positions with one or many partners, purely for the sake of it.
Guy 1). Good night last night?

Guy 2). Yeah man, practised some fucknastics with the missus, nearly snapped cock off!
by mikeland38 January 17, 2011