Etiology is taken from the word Rope-a-dope which in short means to fake someone out.
Generally occurs when you see someone who you think is going to be ghetto, hood, white trash, or a loser and they turn out to be pretty decent, polite, well spoken, and/or professional.
Guy B - "No man. He just has long hair so he kind of looks like a doper"
Guy A - "Man, that fool is a rope-a-dopa!"