sneak mex
A particularly stealthy and sly mexicano man. Can be used to refer to an illegal immigrant, or any mexican who portrays a general sneakyness about him.
Me: Yo look at Pedro over there, he's lookin shady as fuck.

Drew: Ya dude I heard he jumped the fence and hid from the Border Patrol in a barrel for 3 straight days!

Me: Wow, what a god damn sneak mex!