WINDAGE

noun Etymology: 1wind Date: circa 1710 1. the space between the projectile of a smoothbore gun and the surface of the bore, the difference between the diameter of the bore of a muzzle-loading rifled cannon and that of the projectile cylinder, 2. the amount of sight deflection necessary to compensate for wind displacement in aiming a gun, b. the influence of the wind in deflecting the course of a projectile, the amount of deflection due to the wind, the surface exposed (as by a ship) to the wind