\Tra"cing\, n.
1. The act of one who traces; especially, the act of copying
   by marking on thin paper, or other transparent substance,
   the lines of a pattern placed beneath; also, the copy thus
   producted.

2. A regular path or track; a course.

{Tracing cloth}, {Tracing paper}, specially prepared
   transparent cloth or paper, which enables a drawing or
   print to be clearly seen through it, and so allows the use
   of a pen or pencil to produce a facsimile by following the
   lines of the original placed beneath.