When one wears the fly on their pants half zipped. It was an extremely popular style in many high schools between 2004 - 2007. It must be noted that only the most stylistic and iconic figures in the high school social scene can successfully rock the half zip.
Person 1 "Hey bro, your fly is undone."
Person 2 "Nah, man I am rocking the half zip; I am bringing it back."
Person 1 "Man, I wish I was as stylistic and iconic as you."