rude slang A term intended as a humorous and milder replacement for the word "shit" and its wide variety of meanings and applications. A: "I think there might be a problem with your internet connection." B: "No shiznits, Tom." Holy shiznits, I can't believe you actually made it to the party! I thought you were still in Japan! Oh, shiznits—I didn't mean to erase the entire file! That's nearly three hours of work totally down the drain!