To get in the way of so as to hide from sight.
To impede, retard, or interfere with; hinder.
To block or fill (a passage) with obstacles or an obstacle. See synonyms at block.
To sharpen (an image) by creating a blurred ("unsharp") negative as a mask, and then combining that mask with the original.
out of focus; blurry.
dulled or intentionally blunt.