Time of Flight
Also: TOF
The elapsed time a bullet spends in the air to the target, the quantity that underlies both drop and wind drift at any range.
Time of flight is simply how long the bullet is airborne between the muzzle and the target at a given distance. It grows faster than range because the bullet keeps decelerating, so doubling the distance more than doubles the time aloft. That elapsed time is the engine behind the entire trajectory, since gravity has longer to act the longer the bullet flies.
Because of this, time of flight directly sets bullet drop and gives the wind more seconds to push the bullet sideways. It also governs spin drift, which accumulates with time rather than distance. A flatter-shooting load with higher retained velocity reaches the target sooner, which is one reason high-BC bullets are easier to hit with at long range.