sleeper
noun
Simple meaning
That which lies dormant, as a law.
Pronunciation
Say it like this:
sleeperSay the bold part a little louder.
IPA pronunciation (US)
ˈslipɚ
This word is pronounced essentially the same in American and British English, so one transcription covers both.
IPA (International Phonetic Alphabet) is a standard way of writing speech sounds.
Definition
Everyday modern meanings first, grouped by part of speech.
noun
That which lies dormant, as a law.
A spy, saboteur, or terrorist who lives unobtrusively in a community until activated by a prearranged signal; may be part of a sleeper cell.
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
A small starter earring, worn to prevent a piercing from closing.
Something that achieves unexpected success after an interval of time.
“The winner was a true sleeper--no one expected him to get it.”
An unexpected hit
“That movie was the sleeper of the summer.”
Word at a Glance
- Difficulty
- B2 · Upper Intermediate (estimated)
- Frequency
- Moderately Common
- Typical Use
- Varies by meaning
Word Aura™
How this word commonly comes across.
Aura for this meaning
This meaning: That which lies dormant, as a law.
Used this way, sleeper is a specialist word that usually carries little praise or criticism of its own. This is a legal use: the wording is institutional and carries a defined meaning in law rather than a loose everyday one.
- Emotional tone
- Neutral
- Formality
- Specialist/technical
- Intensity
- Not strongly marked
- How common
- Specialized
- Connotation
- Clinical and technical
- Usage feel
- Technical and specialized
Where it naturally appears
- Law/legal
- Government/politics
- Academic writing
Usage note
In general conversation this sense usually needs explaining — outside its field, people reach for a plainer word.
Word Aura describes common impressions, not a measurement. Tone changes with sentence, speaker, relationship and situation.
How It’s Used
The word’s distinct uses, one example each.
Achievesnoun
“The winner was a true sleeper--no one expected him to get it.”
Unexpectednoun
“That movie was the sleeper of the summer.”
More ways to use sleeper
- “The winner was a true sleeper--no one expected him to get it.”noun
- “That movie was the sleeper of the summer.”noun
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Common Patterns and Combinations
How this word naturally appears with others.
Word Family
Related forms, grouped by how they connect.
Compound terms
Established multiword terms.
A cell of sleepers.
Tropical fish that resembles a goby and rests quietly on the bottom in shallow water.
A nest of sleepers awaiting a prearranged signal.
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Dictionary data from Wiktionary via the Free Dictionary API. Simple meanings, combinations and word intelligence are built from verified reference data, no AI is used to load this page.