Dull or dark in colour or brightness.
Dark; gloomy; shadowy, dimly lit.
Melancholic, gloomy, dreary, dismal; grim.
Grave; extremely serious.
To make sombre or dark; to make shady.
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.