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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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