A CASTER is a small wheel, usually made of metal or plastic, that is attached to the bottom of furniture or other objects to allow them to be moved easily. A TRUNDLE is a small wheeled cart or bed frame used for storage or transportation. A ROWEL is a small wheel with radiating points, typically used as a decorative item on horse bridles and spurs. A TRUCKLE is a small wheeled cart or bed frame used for storage or transportation, similar to a TRUNDLE.