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See also: Sleeper



  • (file)
  • Rhymes: -iːpə(r)

Etymology 1[edit]

sleep +‎ -er


sleeper (plural sleepers)

  1. 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.
  2. That which lies dormant, as a law.
    • (Can we date this quote?) 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 []
  3. A spy, saboteur, or terrorist who lives unobtrusively in a community until activated by a prearranged signal; may be part of a sleeper cell.
  4. A railway sleeping car.
    We spent a night on an uncomfortable sleeper between Athens and Vienna.
  5. 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.
  6. A goby-like bottom-feeding freshwater fish of the family Odontobutidae.
  7. A nurse shark (family Ginglymostomatidae).
  8. 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.
  9. (slang) An automobile which 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.
  10. (slang) A sedative.
    • 1995, Faithless (band), Insomnia (song)
      At least a couple of weeks since I last slept,
      Kept takin' sleepers, but now I keep myself pepped.
  11. A small starter earring, worn to prevent a piercing from closing.
Derived terms[edit]


sleeper (third-person singular simple present sleepers, present participle sleepering, simple past and past participle sleepered)

  1. (rare) To mark a calf by cutting its ear.
    • 1963, Jack Schaefer: Monte Walsh, p 81:
      I expect there ain't a trick to maverickin' and sleeperin' and changin' a brand he don't know.

Etymology 2[edit]

Compare Norwegian sleip (a sleeper (a timber); as adjective, slippery, smooth). See slape.


sleeper (plural sleepers)

  1. (rail transport, Britain) A railroad tie.
    The short wooden bars are sleepers, and the long metal bars are rails.
    • 1901, Gipps, George, The Fighting in North China (up to the Fall of Tientsin City), Shanghai: Kelly and Walsh, OL 23299616M, page 40:
      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.
    Synonym: tie (US)
  2. (carpentry) A structural beam in a floor running perpendicular to both the joists beneath and floorboards above.
  3. (nautical) A heavy floor timber in a ship's bottom.
  4. (nautical) The lowest, or bottom, tier of casks.