Plain English Meaning

By the time you're on short final, the airplane should already be doing everything it needs to do for landing: pointed at the runway, at the right speed, flaps and gear set, power set, and coming down steadily. Nothing should still need fixing. If something is off and you can't quickly correct it, you go around.

Full Definition

A method of flying the final approach in which the airplane is established on the proper flightpath, at the proper airspeed, in the proper landing configuration, with the proper power setting, and with a constant rate of descent leading to a normal -- all achieved before reaching a defined on (commonly 500 feet above the runway in , 1,000 feet in conditions). If any of these parameters cannot be maintained within , a is executed.