Aerial Interrupt

Use an aerial attack in a way that causes you to land on a platform which would not have happened without the aerial attack. The reason is a downward shift of your character's environment collision box (ECB) bound to the attack or, more specifically, your character's bone alignment on a given frame.

Sheik performs an aerial interrupt with her up aerial and retains 8 frames of grounded intangibility
Captain Falcon's aerial interrupt, using his back aerial, alternating between normal and hitbox vis.
from Kadano