|an extraordinary or unusual thing, person, or event; an exceptional example or instance.|
|a photocopying process in which an electrostatic image is formed on a selenium plate or cylinder. The plate or cylinder is dusted with a resinous powder, which adheres to the charged regions, and the image is then transferred to a sheet of paper on which it is fixed by heating|
xerography xe·rog·ra·phy (zĭ-rŏg'rə-fē)
any of several image-forming processes, principally xerography and the dielectric process, that rely on photoconductive substances whose electrical resistance decreases when light falls on them; it is the basis of the most widely used document-copying machines.
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