A phrase used to express seriousness, or actuality. When the legitimacy of someone's threatening attitude is challenged, or the realness of an event or sight is questionable, etc., this phrase is used to confirm it. Can be used in place of "for real" or "seriously" or "fo shizzle" or any other phrase of that nature.
Person 1: Girl, I will CUT... YOU...
Person 2: Haha, yeah right..
Person 1: I'm going to cut you. This is real life.