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

Solicitor General Ellie Reeves said: "Vulnerable people, including rough sleepers and veterans, were promised homes, while investors who funded millions of pounds were promised returns. Both groups deserve answers."

From BBC

He previously played a KGB sleeper agent in The Americans, for which he won an Emmy Award for his acting in 2018.

From BBC

Good Shepherd in Wolverhampton supports vulnerable and disadvantaged people in the city, from rough sleepers to families living in supported accommodation.

From BBC

The track’s metaphorical meaning — comparing his own flawed behavior in relationships to a “mutt” or a dog with good intentions — along with a sensual bassline and knocking drums eventually became a sleeper hit.

From Los Angeles Times

Recent research has demonstrated that AI models can harbor sleeper agents that can be triggered under specific conditions without detection.

From The Wall Street Journal

Related Words

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