Harsh or dissonant.
Extremely good at something (usually a video game).
Crazy; crackpot.
Broken into coarse pieces.
Broken so that cracks appear on, or under, the surface.
dulled or intentionally blunt.
out of focus; blurry.
To sharpen (an image) by creating a blurred ("unsharp") negative as a mask, and then combining that mask with the original.