Aerodynamic Jump
A small vertical impact shift caused by the bullet's interaction with crosswind in the first few feet of flight. Measurable at extended range.
When a bullet exits the muzzle into a crosswind, the wind imparts a tiny yaw before the bullet stabilizes. That yaw translates into a vertical impact offset that grows with distance. Left wind generally moves impact up, right wind down (for right-twist barrels).
The effect is small, about 0.05-0.15 mil at 1,000 yards on typical loads. Advanced ballistic calculators (4DOF, AB) account for it, while basic ones leave it out entirely. For ELR work it adds up alongside the other small corrections.