An arrogant kid, around the age of 15-25, who is arrogant and full of themselves. A minsikid is small-minded (min) and will be among the cockiest people you'll ever meet in your life.
Kid #1: God, I am so awesome at basketball, nobody has ever played this game like I have.
Kid #2: Stop being such a minsikid, you got one effing 3 pointer. There is another quarter left in the game.