Derived from the DSM-IV DEVELOPMENTAL DISORDERS diagnosis of Mild Mental Retardation. Typically referred to a person that is not intellectually gifted aka a "mental midget" or "tard".
That guy Bob that works in technical support is a real 317.
by Chaz Finney April 09, 2003
area code for NAPTOWN!! (indianapolis); used as id for home city
I roll from the 317.
by Jonathan Erwin March 23, 2005