⚡ Quick summary
Although the words jail and prison are often used interchangeably in casual use, jail is typically used to refer to smaller, more local facilities, in which people are incarcerated for short periods of time, while prison is used to refer to larger facilities (such as state and federal prisons) in which people are incarcerated for long periods.
The words jail and prison are sometimes used interchangeably, but they can imply different things. Commonly held distinctions relate to the size of the facility and how long someone is being held there.
In this article, we’ll lay out the differences between casual and official use of these words, explain what they often mean in practical terms, and discuss and define similar terms, including penitentiary, detention center, and correctional facility.
What does jail mean?
A jail is a place for the purpose of imprisoning (holding) someone, typically someone who has been convicted of a minor offense or someone who is awaiting trial for the crime they are accused of having committed (or someone who is awaiting a transfer to another detention facility). The word jail implies that the period of incarceration (imprisonment or confinement) is relatively short, and that the facility itself is somewhat small—perhaps only having a handful of cells.
Such facilities are often those below the level of a state or federal facility, such as a county jail. The word jail is also likely to be used in reference to even smaller facilities, such as the cells at a local police station.
The phrase in jail can refer to being confined in such a place specifically, but it’s more often used in a general way to simply indicate that someone is incarcerated, regardless of what kind of facility they’re being held in, as in If he’s convicted, he’ll be in jail for at least 10 years.
The word jail is also used to refer to the consequence of incarceration, as in If we get caught, it’ll be jail for both of us.
Jail is also used as a verb meaning to put or hold someone in jail, as in She was jailed for 10 days while awaiting trial.
What does prison mean?
A prison is also a place where people are incarcerated, but the word usually implies a large facility for those serving long-term sentences. In the US, state and federal facilities are usually called prisons, as in state prison or federal prison.
The phrase in prison usually specifically indicates that a person is in such a facility, as opposed to being generally incarcerated (as is usually indicated by the phrase in jail).
The verb imprison means to place or hold someone in prison. The noun imprisonment refers to the state of being held in prison or to the act of imprisoning someone.
What do penitentiary, detention center, and correctional facility mean?
Places of incarceration aren’t always called prisons or jails. State and federal prisons are often called penitentiaries. The term correctional facility can refer to a prison and is used in the name of some prisons. The term detention center is sometimes used in a general way, but it is also used more specifically to refer to facilities with functions other than long-term imprisonment, such as holding immigrants awaiting deportation hearings or witnesses before a trial.
What’s the difference between jail and prison?
While the words can overlap, prison is more likely to be called jail than jail is to be called prison. That’s because jail can be used as a more general term, especially in phrases like going to jail or in jail (which imply incarceration regardless of how long it is).
Still, calling a facility a jail typically implies that it’s relatively small, local, and for short-term periods of incarceration—a county jail. Calling a facility a prison, on the other hand, implies a large facility for the confinement of people who have been convicted of crimes and are serving long-term sentences—a state or federal prison.
