The phrase 'stack the deck' or 'stack the cards' has been around for about two hundred years. The simple verb 'to stack' has been around for a lot longer, of course. It means to place things one on top of the other, in an organised way, as in creating a hay-stack. It's the idea of 'organisation' that is the key, because - if the game is to be fair - the position of cards should be absolutely random.