A slurshie is slang for a 7-11 slurpee. Originated by Mark B. and widely accepted by his minions (aka Eric M.)
Hey bro, you want to go get a slurshie and play some halo?
A slurshie is a 7-11 slurpee with alcohol in it. perferably rum.
Hey, do you want to make a slurshie before we head over to the party?