Point of Impact
Also: POI
Where the bullet actually lands on the target. Compared against the point of aim to evaluate the shot and to confirm a rifle's zero from a cluster.
The honest measurement of a shot. A perfect call (POI = POA exactly) is rare past 600 yards. Even excellent shooters routinely accept impacts within a small radius of POA as good calls.
For zero verification, multiple POIs cluster around the desired zero distance impact. The center of that cluster, not any single shot, is your real zero.