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English definition of “sleeper”


noun [C]    /ˈsli·pər/
a sleeping person: He is a very light sleeper (= he wakes easily). A sleeper is also a person or thing that is unexpectedly successful: We almost gave up on this line of merchandise, but it's a real sleeper – it keeps selling.
(Definition of sleeper noun from the Cambridge Academic Content Dictionary © Cambridge University Press)
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