Usually a prison or corrections facility will append a suffix to it’s title to help better categorize the purpose of the institution. Here are what some of the common prison acronym suffixes stand for.

Atwater U.S. Penitentiary
CI – Correctional Institution (a private facility)
CO – Central Office
DC – Detention Center (a private facility)
FCC – Federal Correctional Complex
FCI – Federal Correctional Institution
FDC – Federal Detention Center
FMC – Federal Medical Center
FPC – Federal Prison Camp
FTC – Federal Transfer Center

Alderson Federal Prison Camp
MCFP – Medical Center for Federal Prisoners
MDC – Metropolitan Detention Center
RO – Regional Office
RRC – Residential Reentry Center
USP – U.S. Penitentiary