The situation that occurs when a man's penile shaft appears ridiculously small when flacid, but grows to an abnormal, if not surprising size when erect.
Michael's penis was 2 inches long when he was at his grandma's house, but later as he watched gay porn, his penile shaft grew to an impressive 10 inches. Michael experienced the Accordian Effect.
by Ellikay48 September 24, 2007