sleeper

American  

[slee-per] / ˈsli pər /

noun

1. a person or thing that sleeps.

2. a heavy horizontal timber for distributing loads.

3. Building Trades.

   1. any long wooden, metal, or stone piece lying horizontally as a sill or footing.

   2. any of a number of wooden pieces, laid upon the ground or upon masonry or concrete, to which floorboards are nailed.

4. a sleeping car.

5. Informal. something or someone that becomes unexpectedly successful or important after a period of being unnoticed, ignored, or considered unpromising or a failure.

   The play was the sleeper of the season.

6. merchandise that is not quickly sold because its value is not immediately recognized.

7. Often sleepers. one-piece or two-piece pajamas with feet, especially for children.

8. bunting.

9. a sofa, chair, or other piece of furniture that is designed to open up or unfold into a bed; convertible.

10. Also called sleep, sand.  a globule that forms at the inner corner of the eye, especially during sleep, from the accumulated secretion of the glands of the eyelid.

11. any of several gobioid fishes of the family Eleotridae, of tropical seas, most species of which have the habit of resting quietly on the bottom.

12. Slang. a spy; mole.

13. Slang. a juvenile delinquent sentenced to serve more than nine months.

14. Bowling. a pin that is hidden from view by another pin.

15. Chiefly British. a timber or beam laid in a railroad track, serving as a foundation or support for the rails; tie.

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sleeper British  

/ ˈsliːpə /

noun

1. a person, animal, or thing that sleeps

2. a railway sleeping car or compartment

3. US and Canadian equivalent: tie.  one of the blocks supporting the rails on a railway track

4. a heavy timber beam, esp one that is laid horizontally on the ground

5. a small plain gold circle worn in a pierced ear lobe to prevent the hole from closing up

6. a wrestling hold in which a wrestler presses the sides of his opponent's neck, causing him to pass out

7. an unbranded calf

8. Also called: sleeper goby.  any gobioid fish of the family Eleotridae, of brackish or fresh tropical waters, resembling the gobies but lacking a ventral sucker

9. informal a person or thing that achieves unexpected success after an initial period of obscurity

10. a spy planted in advance for future use, but not currently active

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Etymology

Origin of sleeper

Middle English word dating back to 1175–1225; sleep, -er ¹

Example Sentences

"This suggests that dreaming may reshape how brain activity is interpreted by the sleeper: the more immersive the dream, the deeper the sleep feels."

From Science Daily

Teo was a good sleeper and she enjoyed the days spent caring for her baby son while on maternity leave.

From BBC

Still, federal authorities warned local law enforcement that they had detected a new broadcast of a likely encoded sequence that could be “an operational trigger” for “sleeper assets” potentially on U.S. soil.

From Los Angeles Times

These alarm clocks have novel ways to rouse deep sleepers.

From The Wall Street Journal

Product designers are coming up with novel ways to rouse deep sleepers that border on diabolical, including clocks that deliver 300-volt electric shocks and donate snoozers’ money to charity.

From The Wall Street Journal

Related Words

• agent
• detective
• informer
• investigator
• mole
• operative
• secret agent
• secret service
• undercover agent