Expect to get your drink order out in three words or less next year, as cocktails get much simpler.

Millennials grew up in the era of fancy drinks that included several ingredients, but now the cool drinks are more like what their grandparents ordered.

"We are going to move to a simple cocktail that isn't fancy or require waiting a long time at the bar," said Freeman. "I am talking the three-ingredient drink."

He pointed to the Old Fashioned as a contender for the drink of 2015.