Noun

(en noun)

Someone who sleeps.

I'm a light sleeper : I get woken up by the smallest of sounds.

She's a heavy sleeper : it takes a lot to wake her up.

That which lies dormant, as a law.

* Francis Bacon

Therefore let penal laws, if they have been sleepers of long, or if they be grown unfit for the present time, be by wise judged confined in the execution

A spy, saboteur, or terrorist who lives unobtrusively in a community until activated by a prearranged signal; may be part of a sleeper cell.

A railroad sleeping car.

We spent a night on an uncomfortable sleeper between Athens and Vienna.

Something that achieves unexpected success after an interval of time.

A box-office bomb when it first came out, the film was a sleeper , becoming much more popular decades after being released.

A goby-like bottom-feeding freshwater fish of the family .

A nurse shark.

A type of pajama for a person, especially a child, that covers the whole body, including the feet.

Aaron, Devin, and Laura looked so comfy in their sleepers .

(slang) An automobile which, not too quick out of the factory, has been internally modified to excess, while retaining a mostly stock appearance in order to fool opponents in a drag race, or to avoid the attention of the police.

Noun

(en noun)

(rail transport, British) A railroad tie.

* {{quote-book

, year = 1901 , title = The Fighting in North China (up to the Fall of Tientsin City) , first = George , last = Gipps , location = Shanghai , publisher = Kelly and Walsh , ol = 23299616M , page = 40 , pageurl = http://archive.org/stream/fightinginnorthc00gipp

page/40/mode/2up

, passage = The train, minus the three abandoned trucks, again proceeded at a slow pace, with a pump trolley doing pilot ahead ; this was very necessary as a great many sleepers were found to have been burnt underneath the fishplates. }}

(carpentry) A structural beam in a floor running perpendicular to both the joists]] beneath and [[floorboard, floorboards above.

(nautical) A heavy floor timber in a ship's bottom.

(nautical) The lowest, or bottom, tier of casks.