Sentence:  The <WSD>area</WSD> adjacent to one edge of a piece of affixed material - or simply of a painted in form - will be shaded to pry that edge away from the surface , while something will be drawn , painted or even pasted over another part of the same shape to drive it back into depth . 
Meaning of the word marked with <WSD> tags:  a particular geographical region of indefinite boundary (usually serving some special purpose or distinguished by its people or culture or geography)