A type of mixed drink made by first purchasing a Wendy's frosty and then mixing in some type of hard liquor, preferably rum. Refers to any type of alcoholic mixed drink that involves a Wendy's frosty.
person 1: we need to go to wendy's dude and get a frosty!
person 2: why the fuck do you want a frosty? you some kind of punk bitch?
person 1: nah im gonna make a wendy blendy so fuck you, go eat a dick.