A drink only found at McDonald's from a special request: Half Shamrock Shake and Half Chocolate. Very tasty. Originated in Wisconsin.
Person 1: Hey, where do you want to eat tonight?
Person 2: Let's hit up McDonald's and get some Dirty Shams.
Person 2: Let's hit up McDonald's and get some Dirty Shams.
by DasWxMan April 17, 2013
Get the Dirty Shammug.