touchback - (American football) a play in which the opposing team has kicked the football into your end zone.
From Wikipedia, the free encyclopedia. A check digit is a form of redundancy check used for error detection on identification numbers, such as bank account numbers, which are used in an application where they will at least sometimes be input manually. It is analogous to a binary parity bit used to check for errors in computer-generated data.
A bank routing number or routing transit number (RTN, ABA) is a 9 digit number that identifies the location where your account was opened. You'll often be asked for your checking account routing number when you're making a payment online or by phone.