n.
a rester who is sleeping
同义词：slumberer
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
an unexpected achiever of success
"the winner was a true sleeper--no one expected him to get it"
one of the cross braces that support the rails on a railway track
"the British call a railroad tie a sleeper"
同义词：tierailroad tiecrosstie
a passenger car that has berths for sleeping
同义词：sleeping carwagon-lit
pajamas with feet; worn by children
a piece of furniture that can be opened up into a bed
tropical fish that resembles a goby and rests quietly on the bottom in shallow water
同义词：sleeper goby
an unexpected hit
"that movie was the sleeper of the summer"
