Used to describe the prevailing tone of a painting. A predominantly light painting is said to have a high key. In contemporary mural painting, the key is the result of scratching a walls surface to prepare for final layer of plaster - similar to "tooth"<br><br>The lighness (high key) or darkness (low key) of a painting.<br><br>(1) The screw that controls ink flow from the ink fountain of a printing press. (2) To relate loose pieces of copy to their positions on a layout or mechanical using a system of numbers or letters. (3) Alternate term for the color black, as in &#39;key plate.&#39;<br><br>Piece of wood, which fits into the corners of a stretcher to maintain the tension of the canvas. Key Examples <br><br>A small interlocking device in the seam of a mold, enabling the mold to be precisely reassembled. The term may also refer to the slight roughening of a surface which allows a painted finish to adhere effectively.Also, it&#39;s a name given to wedges that stabilize canvas stretchers.These can be seen here, driven into the interlocking corners of wooden stretcher bars to produce tension on canvas support.To "key out" is to increase the outward stretch of the stretcher bars. A painting on canvas should always remain taut, but a painting that shows bulges can often be flattened by keying out the stretchers. A painting can be keyed out excessively. On a humid day a canvas might be so tightly stretched that when the humidity decreases it can rip apart. Old paintings on wooden frames with no keys or frames of other materials are often replaced with stretchers that can be keyed out.In architecture, "key" refers to the keystone at the top of an arch.Also see join.