Dispart

noun

1. In gunnery: The difference between the semi-diameter of the base-ring at the breech of a gun and that of the ring at the swell of the muzzle.
2. A dispart-sight.
3. To divide into parts; separate; sever.
4. In gunnery: To set a mark on the muzzlering of, as a piece of ordnance, so that a sight-line from the top of the base-ring to the mark on or near the muzzle may be parallel to the axis of the bore or hollow cylinder.
5. To make allowance for the dispart in, when taking aim.