Short and much more to-the-point form of "standard". Mostly used among highly sophisticated individuals to define and applaud acts of normality. "Standy" can be used as both a noun and an adjective. A common phrase that stems from this term is 'Standy the Boy.'
This idiom does a nice job of simplifying the following: 'Wow, I just acknowledged how typical you are being at this moment and because of this, I will give you my approval and praise!'
Bob: "Hey Jeremy, did the Leafs win today?"
Jeremy: "They almost came back in the 3rd"
Alex: "I just got 100% on my chemistry midterm!"
Tyler: "Standy the boy!"
Hans: "Shit I just found out my midterm is in 3 hours"
Gordon: "Whoa, are you gonna study for it?"
Hans: "Nope gonna pull a standy"