The Collaborative International Dictionary of English v.0.48:

Trace \Trace\, v. t. [imp. & p. p. traced; p. pr. & vb. n.
   tracing.] [OF. tracier, F. tracer, from (assumed) LL.
   tractiare, fr.L. tractus, p. p. of trahere to draw. Cf.
   Abstract, Attract, Contract, Portratt, Tract,
   Trail, Train, Treat. ]
   1. To mark out; to draw or delineate with marks; especially,
      to copy, as a drawing or engraving, by following the lines
      and marking them on a sheet superimposed, through which
      they appear; as, to trace a figure or an outline; a traced
      drawing.
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            Some faintly traced features or outline of the
            mother and the child, slowly lading into the
            twilight of the woods.                --Hawthorne.
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   2. To follow by some mark that has been left by a person or
      thing which has preceded; to follow by footsteps, tracks,
      or tokens. --Cowper.
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            You may trace the deluge quite round the globe. --T.
                                                  Burnet.
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            I feel thy power . . . to trace the ways
            Of highest agents.                    --Milton.
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   3. Hence, to follow the trace or track of.
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            How all the way the prince on footpace traced.
                                                  --Spenser.
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   4. To copy; to imitate.
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            That servile path thou nobly dost decline,
            Of tracing word, and line by line.    --Denham.
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   5. To walk over; to pass through; to traverse.
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            We do tracethis alley up and down.    --Shak.
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The Collaborative International Dictionary of English v.0.48:

Tracing \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.
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   2. A regular path or track; a course.
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   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.
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WordNet (r) 3.0 (2006):

tracing
    n 1: the act of drawing a plan or diagram or outline
    2: a drawing created by superimposing a semitransparent sheet of
       paper on the original image and copying on it the lines of
       the original image [syn: tracing, trace]
    3: the discovery and description of the course of development of
       something; "the tracing of genealogies"

Moby Thesaurus II by Grady Ward, 1.0:

84 Moby Thesaurus words for "tracing":
   apograph, black and white, brouillon, carbon, carbon copy, cartoon,
   charcoal, charcoal drawing, chiaroscuro, companion, copy, crayon,
   dead ringer, delineation, design, diagram, doodle, double, draft,
   drawing, duplicate, duplication, ebauche, effigy, esquisse,
   exact likeness, fellow, fiche, graph, hectography, icon, idol,
   image, likeness, line drawing, living image, living picture,
   manifold, match, mate, microcopy, microfiche, microform,
   mimeography, miniature, mirroring, model, pastel, pen-and-ink,
   pencil drawing, photograph, picture, portrait, recording,
   reduplication, reflection, reproduction, reprography, resemblance,
   rough copy, rough draft, rough outline, rubbing, semblance, shadow,
   silhouette, silver-print drawing, similitude, simulacrum, sinopia,
   sketch, spit and image, spitting image, study, tenor, trace,
   transcript, transcription, transfer, twin, very image,
   very picture, vignette, xerography