A grazing angle is almost parallel to the surface.
Is there another word for an angle almost perpendicular to the surface?
(Or is that just it?)
There is oblique : Designating geometric lines or planes that are neither parallel nor perpendicular.
So an "oblique hit" would be an impact with a higher angle of incidence than your "grazing hit" but would not be a true perpendicular hit.
Consider near-normal, where normal means “(geometry) A line or vector that is perpendicular to another line, surface, or plane”, and also consider off-plumb, where plumb means “truly vertical” or “(informal) Squarely, directly; completely”.