For just some historical purposes, here was the wording in the 2002 NCAA rule book
Rule 4
Section 1. Airborne Shooter
Art. 1. An airborne shooter is a player who has released the ball on a try for goal until one foot has returned to the floor.
Even as late as 2007, the rule mentioned an airborne player being one until one foot returned to the floor. Starting in 2008, it was changed to the wording which just mentioned he's an airborne shooter until he returns to the floor.