What is meant by trajectory in firearms terminology?

Trajectory in firearms terminology refers to the curved path that a projectile follows during its flight from the moment it leaves the muzzle until it reaches the target. Understanding trajectory is crucial for effective marksmanship and targeting, as it is influenced by various factors including gravity, air resistance, and the initial velocity of the projectile. Knowledge of trajectory allows shooters to compensate for drop and windage when aiming at targets, particularly at longer ranges where these factors become more pronounced.

The other concepts mentioned in the options, such as the angle of the barrel at firing, the speed of the projectile, and the total distance traveled by the round, represent different aspects of ballistics but do not capture the notion of trajectory itself. This makes the understanding of trajectory vital for anyone involved in shooting or tactical operations.