Joint

  meaning : a prison, a jail

For example:

• My cousin Henry has been in the joint for the last three years, but he might get out on parole next year.
  
• After he got out of the joint, Sammy had a lot of trouble finding a job. Most people won't hire someone who just got out of jail.

Note: usually used with the definite article, as in "the joint"

Variety: This slang is typically used in American English but may be used in other varieties of English too.