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.
1 more example
Waveless mattresses are for those who prefer a more stationary [night's sleep]; semiwaveless for those who want a slight rocking motion, and free-flow for sleepers who want the feel of a boat. All beds come with temperature controls, and king- and queen-size models offer dual controls.1986 August 28, Patricia Leigh Brown, “17 YEARS OF THE WATER BED: A SOCIAL HISTORY; CHECKING OUT REFINEMENTS”, in The New York Times, archived from the original on 03 Feb 2018:
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That which lies dormant, as a law.
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 […]1625, Francis [Bacon], “Of Judicature”, in The Essayes […], 3rd edition, London: […] Iohn Haviland for Hanna Barret, →OCLC:
The object of these provisions is to prevent insertion of "jokers" or "sleepers" in bills and securing passage under the false color of the title.1958, Duncan Leroy Kennedy, Bill drafting, page 12:
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A spy, saboteur, or terrorist who lives unobtrusively in a community until activated by a prearranged signal; may be part of a sleeper cell.
We are up against the pros; and pros who have been involved in this kind of activity for many years. […] The public apathy today is disturbing — few realize, Mr. Chairman, that there are sleepers in this country and we know that they are able to manipulate at will behind the scenes.1969, United States Congress, Departments of Treasury and Post Office and Executive Office Appropriations for 1970: Hearings, (91st Congress, First Session, parts 2-3), page 479:
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A small starter earring, worn to prevent a piercing from closing.
His skull earring had been replaced by a small gold sleeper. […] Fiona, who also had pierced ears, remarked on his sleeper. “Doesn’t Wilton allow pierced ears?” she asked. “No way!” said Leslie. “Rules about everything. But I wanted to keep my options open, as you might say. No one’s made me take it out yet. […]”1984, Diana Wynne Jones, Fire and Hemlock:
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A railway sleeping car.
We spent a night on an uncomfortable sleeper between Athens and Vienna.
It is realised that the old Pullman standard sleeper, with its convertible "sections", each containing upper and lower berths, and with no greater privacy at night than the curtains drawn along both sides of a middle aisle, has had its day.1944 November and December, “"Duplex Roomette" Sleeping Cars”, in Railway Magazine, page 324:
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.
For example, the [racehorse] trainer may have tipped a betting syndicate that he is about to unleash a sleeper […]1968, Marvin B. Scott, The Racing Game, page 160:
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Any of family Odontobutidae of goby-like bottom-feeding freshwater fish.
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A nurse shark (family Ginglymostomatidae).
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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.
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Automotive, Transport, VehiclesSlang 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.
At least a couple of weeks since I last slept, / Kept takin' sleepers, but now I keep myself pepped.1995, “Insomnia”, in Reverence, performed by Faithless:
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Gambling, GamesSlang A bet placed on the gambling table and then forgotten about by the gambler.
"There," she said to herself, looking into the shadow of the carriage, at the sand and coal dust which covered the sleepers— "there, in the very middle, and I will punish him and escape from everyone and from myself."1901 [1878], chapter 31, in Constance Garnett, transl., Anna Karenina, translation of Анна Каренина (Anna Karenina) by Leo Tolstoy, part 7:
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.1901, George Gipps, The Fighting in North China (up to the Fall of Tientsin City), Shanghai: Kelly and Walsh, →OL, page 40:
2 more examples
I should imagine that the smooth riding and the quietness of the diesel or electric cab, coupled with the effect on the eyes of endless successions of sleepers disappearing from sight immediately under the driver's eyes, might in time have a soporific effect, so that the company of a second man, who can assist in signal observations when he is not at work in the engine cab, seems highly desirable in such conditions.1961 July, Cecil J. Allen, “Locomotive Running Past and Present”, in Trains Illustrated, page 401:
Government surveyors set to work, importing hundreds of Indian coolies, thousands of donkeys and camels, and the millions of sleepers required for this monstrous engineering project.2009, Michela Wrong, It’s Our Turn to Eat: The Story of a Kenyan Whistle Blower: