To be under the influence of cannabis. A combination of spliff (a joint) and lifted (the results of smoking a joint). Splifted is used to describe the mind state of being very, very stoned.
Joe: Word up holmes, I just finished my final exam and it's time to celebrate. Match up?
Fred: Sure, I'll hit up Doobies after school, grab a blunt wrap, call the dopeman, and we'll get splifted!
Ex. 1
Alan: "How's this one compared to the last one?"
Brian: "Can we splifference between the two?"
Ex. 2
Alan: "Do you want me to hook you up with someone like Tiffany, or someone like Jasmine?"
Brian: "Tiffany's legs are like nom nom nom nom nom, but Jasmine's chest is like BAM! Can you splifference it?"