Noun

1. A place of long-term confinement for those convicted of serious crimes.

   The cold stone walls of the prison had stood for over a century.

2. Confinement in a prison.

   Prison was a harrowing experience for him.

3. Any restrictive environment, such as a harsh academy or home.

   The academy was a prison for many of its students because of its strict teachers.

Synonyms

• (place): gaol, jail, bridewell. See Wikisaurus:jail.
• (confinement): imprisonment