Definition of sleeper
1 : one that sleeps
2 : a piece of timber, stone, or steel on or near the ground to support a superstructure, keep railroad rails in place, or receive floor joists : stringpiece
3 : sleeping car
4 : someone or something unpromising or unnoticed that suddenly attains prominence or value the low-budget film became the summer's sleeper
5 : children's pajamas usually with feet —usually used in plural
6 chiefly British : a small earring or stud worn to keep the hole of a pierced ear from closing
7 : 2mole 4
Examples of sleeper in a sentence
Sleepers were awakened by the sound of a loud crash.
He may turn out to be the sleeper in this year's election.
The movie was the summer's sleeper.
The movie became the sleeper hit of the summer.
First Known Use of sleeper
SLEEPER Defined for English Language Learners
Definition of sleeper for English Language Learners
: a person who sleeps in a particular way
: someone who is asleep
: a place or piece of furniture that can be used for sleeping
SLEEPER Defined for Kids
Definition of sleeper for Students
1 : someone that sleeps I'm a light sleeper.
2 : a railroad car with berths for sleeping
Seen and Heard
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