1.  windage(n = noun.phenomenon) Array - the retarding force of air friction on a moving object; Array
is a kind of drag, retarding force

2.  windage(n = noun.attribute) Array - the space between the projectile of a smoothbore gun and the surface of the bore of the gun; Array
is a kind of diam, diameter

3.  windage(n = noun.attribute) wind exposure - exposure to the wind (as the exposed part of a vessel's hull which is responsible for wind resistance); Array
is a kind of exposure

4.  windage(n = noun.attribute) wind deflection - the deflection of a projectile resulting from the effects of wind; Array
is a kind of bending, deflection, deflexion

1.  The difference between the diameter of the bore of a gun and that of the shot fired from it. [1913 Webster]

2.  The sudden compression of the air caused by a projectile in passing close to another body. [1913 Webster]

windage, n.
1 the friction of air against the moving part of a machine.
2 a the effect of the wind in deflecting a missile. b an allowance for this.
3 the difference between the diameter of a gun's bore and its projectile, allowing the escape of gas.