SLEEPER

noun Date: 12th century one that sleeps, a piece of timber, stone, or steel on or near the ground to support a superstructure, keep railroad rails in place, or receive floor joists ; stringpiece , sleeping car , someone or something unpromising or unnoticed that suddenly attains prominence or value , children's pajamas usually with feet, a small earring or stud worn to keep the hole of a pierced ear from closing, mole 4