An initialism of "three-finger salute," referring to the computer keystroke control-alt-delete, commonly used to force programs to close or the computer to restart in the Windows operating system. (A jocular play on the expression "one-finger salute," referring to the raising of the middle finger, a rude gesture commonly called "the finger.") This computer is so janky that I have to give it the TFS pretty much every day. If the program is still hung up at this stage, you'll probably have to resort to a TFS to shut it down.