sleeper Meaning, Definition & Usage

noun a rester who is sleeping
slumberer.
noun a spy or saboteur or terrorist planted in an enemy country who lives there as a law-abiding citizen until activated by a prearranged signal
noun an unexpected achiever of success
- the winner was a true sleeper--no one expected him to get it
noun one of the cross braces that support the rails on a railway track
tie; crosstie; railroad tie.
- the British call a railroad tie a sleeper
noun a passenger car that has berths for sleeping
wagon-lit; sleeping car.
noun pajamas with feet; worn by children
noun a piece of furniture that can be opened up into a bed
noun tropical fish that resembles a goby and rests quietly on the bottom in shallow water
sleeper goby.
noun an unexpected hit
- that movie was the sleeper of the summer

One who sleeps; a slumberer; hence, a drone, or lazy person.
That which lies dormant, as a law. Obs. Bacon.
A sleeping car. Colloq. U.S.
(Zoöl.) An animal that hibernates, as the bear.
(Zoöl.) (a) A large fresh-water gobioid fish (Eleotris dormatrix). (b) A nurse shark. See under Nurse.

Cf. Norw. sleip a sleeper (a timber), as adj., slippery, smooth. See Slape.

Something lying in a reclining posture or position. Specifically: -- (a) One of the pieces of timber, stone, or iron, on or near the level of the ground, for the support of some superstructure, to steady framework, to keep in place the rails of a railway, etc.; a stringpiece. (b) One of the joists, or roughly shaped timbers, laid directly upon the ground, to receive the flooring of the ground story. U.S. (c) (Naut.) One of the knees which connect the transoms to the after timbers on the ship's quarter. (d) (Naut.) The lowest, or bottom, tier of casks.