noun
Uncommon
sleeper
SLEE-puh
Sleeper (noun) means someone who is sleeping. Example: “She's a light sleeper — the slightest noise wakes her up.”
noun
1
Someone who is sleeping.
"She's a light sleeper — the slightest noise wakes her up."
2
A spy or agent who lives an ordinary life in a community until activated for a mission.
"The film follows a Cold War sleeper waiting years for a single coded message."
3
Something — a film, product, or competitor — that unexpectedly becomes a big success after being overlooked.
"The low-budget film became a sleeper hit, earning ten times its budget."
4
(British) A wooden or concrete beam laid under railway tracks to support them; a railroad tie.
"Workers replaced the rotting sleepers along that stretch of track."
5
A car that has been heavily modified for performance while still looking ordinary.
"His beat-up sedan was a total sleeper — it could outrun most sports cars off the line."
How to use sleeper
Learner’s notesIn plain EnglishSomeone or something asleep, dormant, or hidden — until it unexpectedly succeeds or gets activated.
UK vs US
"Sleeper" for a railroad tie is standard British usage; American English calls the same thing a "tie."
Common pairings
sleeper cell
sleeper hit
railway sleeper
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Word forms
- Plural
- sleepers
- Third person singular
- sleepers
- Past tense
- sleepered
Fill the gap
Can you complete this real example?
She's a light _____ — the slightest noise wakes her up.
Etymology
Formed from "sleep" plus the agent suffix "-er," originally just meaning "one who sleeps."
Synonyms
View more →Related words
Rhymes for sleeper
leper
keeper
peeper
beeper
sweeper
creeper
steeper
beekeeper
innkeeper
zookeeper
goalkeeper
shopkeeper
See all rhymes for sleeper →
Frequently asked questions
What does “sleeper” mean?
The word “sleeper” means someone who is sleeping. In plain terms, someone or something asleep, dormant, or hidden — until it unexpectedly succeeds or gets activated.
How do you pronounce “sleeper”?
“Sleeper” is pronounced SLEE-puh (/ˈsliːpə(ɹ)/ in IPA).
How do you use “sleeper” in a sentence?
Here is “sleeper” used in a sentence: “She's a light sleeper — the slightest noise wakes her up.”
What part of speech is “sleeper”?
“Sleeper” is a noun.
Is “sleeper” a common word?
“Sleeper” is an uncommon word in modern English.
How many meanings does “sleeper” have?
“Sleeper” has 5 distinct senses listed in this dictionary. The most common is: someone who is sleeping.
