Meaning: A small, round piece of metal used as money moved along a surface by turning over and over in a lower position than a piece of furniture for sitting on.
Choice of Words: The word "coin" refers to a small, round piece of metal used as money. "Rolled" means to move along a surface by turning over and over. "Under" means in a lower position than something else. "Couch" is a piece of furniture for sitting on.