a person or animal who is asleep or who sleeps in a specified way
he was a light sleeper, for long periods an insomniac
a train carrying sleeping cars
we were waiting for the Inverness–London sleeper
a sleeper train
a film, book, play, etc. that eventually achieves unexpected success after initially attracting very little attention
this low-budget, black-and-white American sleeper concerns two brothers
it became one of the sleeper hits of the year
a ring or post worn in a pierced ear to keep the hole from closing
a wooden or concrete beam laid transversely under railway track to support it
a stocky fish with mottled coloration which occurs widely in warm seas and fresh water