A sleeper is something that succeeds when no one thought it would. That low-tech movie about shark attacks that you shot on vacation and edited in your basement? It could be a sleeper if you market it in the right way.

You probably know that sleeper can be used in an obvious sense to refer to someone who is asleep. But you also may hear the word used to describe something that becomes an unexpected success, like "a sleeper of a film" featuring unknown actors that ends up becoming the big summer hit. This sense of the word may have originated in the world of gambling in the nineteenth century. When a card player unexpectedly drew a winning card, the card was called "a sleeper."

Definitions of sleeper
  1. noun
    a rester who is sleeping
    synonyms: slumberer
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    someone who is dreaming
    Rip van Winkle
    a person who sleeps a lot
    sleeping beauty
    a person who is sleeping soundly
    noctambulist, sleepwalker, somnambulist
    someone who walks about in their sleep
    someone who snores while sleeping
    someone who talks while asleep
    type of:
    a person who rests
  2. noun
    a passenger car that has berths for sleeping
    synonyms: sleeping car, wagon-lit
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    type of:
    carriage, coach, passenger car
    a railcar where passengers ride
  3. noun
    a piece of furniture that can be opened up into a bed
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    type of:
    article of furniture, furniture, piece of furniture
    furnishings that make a room or other area ready for occupancy
  4. noun
    pajamas with feet; worn by children
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    type of:
    jammies, pajama, pj's, pyjama
    (usually plural) loose-fitting nightclothes worn for sleeping or lounging; have a jacket top and trousers
  5. noun
    an unexpected achiever of success
    “the winner was a true sleeper--no one expected him to get it”
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    type of:
    achiever, succeeder, success, winner
    a person with a record of successes
  6. noun
    an unexpected hit
    “that movie was the sleeper of the summer”
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    type of:
    bang, hit, smash, smasher, strike
    a conspicuous success
  7. noun
    a spy or saboteur or terrorist planted in an enemy country who lives there as a law-abiding citizen until activated by a prearranged signal
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    type of:
    diversionist, saboteur, wrecker
    someone who commits sabotage or deliberately causes wrecks
    spy, undercover agent
    (military) a secret agent hired by a state to obtain information about its enemies or by a business to obtain industrial secrets from competitors
    a radical who employs terror as a political weapon; usually organizes with other terrorists in small cells; often uses religion as a cover for terrorist activities
  8. noun
    one of the cross braces that support the rails on a railway track
    synonyms: crosstie, railroad tie, tie
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    type of:
    brace, bracing
    a structural member used to stiffen a framework
  9. noun
    tropical fish that resembles a goby and rests quietly on the bottom in shallow water
    synonyms: sleeper goby
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    type of:
    percoid, percoid fish, percoidean
    any of numerous spiny-finned fishes of the order Perciformes
Word Family

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