Detain vs Imprison

When to use each in English, with meaning, register, and examples.

Detain

FormalTop 2,000 (common)C1verb

Imprison

FormalTop 5,000 (fairly common)C1verb
Most common: Detain
 DetainImprison
Pronunciation🇬🇧 /["/dɪˈteɪn/","/dɪˈteɪnz/","/dɪˈteɪnd/","/dɪˈteɪnɪŋ/"]/🇺🇸 /["/dɪˈteɪn/","/dɪˈteɪnz/","/dɪˈteɪnd/","/dɪˈteɪnɪŋ/"]/🇬🇧 /["/ɪmˈprɪzn/","/ɪmˈprɪznz/","/ɪmˈprɪznd/","/ɪmˈprɪznɪŋ/"]/🇺🇸 /["/ɪmˈprɪzn/","/ɪmˈprɪznz/","/ɪmˈprɪznd/","/ɪmˈprɪznɪŋ/"]/
MeaningTo keep someone in a place, usually by the police, so they cannot leave.To put someone in jail.
ExampleThe police decided to detain the suspect for further questioning.They were imprisoned for a crime they didn't commit.
RegisterFormalFormal
How commonTop 2,000 (common)Top 5,000 (fairly common)
CEFR levelC1C1
Part of speechverbverb
Collocationsbriefly, indefinitely, illegally, need not, for, in connection with, be detained in custody, be detained in hospital, detain somebody without chargefalsely, unjustly, wrongfully, for, in
Antonymsrelease, free, liberaterelease, free, liberate
Common mistakesConfused with 'retain' which means to keep possession of something., Using 'detain' when referring to someone simply waiting, instead of being held by authority., Incorrectly using 'detain' without specifying who is being detained.Confused with 'prison' — 'imprison' is a verb., Using 'imprisoned' without an object, which can sound incomplete., Mixing it with informal terms in serious discussions.
Usage notesUsed in legal and police contexts. Be careful using it informally; it's not common in everyday conversations about delays or waiting.Use 'imprison' in legal or serious contexts. Avoid using it in casual conversation; instead, say 'put in jail' for informal situations.

Frequently asked questions: Detain vs Imprison

What's the difference between Detain and Imprison?

Detain: To keep someone in a place, usually by the police, so they cannot leave. Imprison: To put someone in jail.

Which is more common: Detain and Imprison?

Detain is the most common in everyday English.

Are Detain and Imprison the same CEFR level?

Detain: C1, Imprison: C1 on the CEFR scale.

Can I use Detain and Imprison interchangeably?

Not always. Detain and Imprison are related and overlap in some contexts, but they differ in register, how common they are, and usage, so swapping one for another can change the meaning or tone. Check the differences above before substituting.

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