1. v - The act of Tracing something. Originally, using tracing paper laid over a drawing or pattern to make a copy. More often now days the use of an Overhead projector, video projector, or Opaque projector to transfer a drawing from paper onto a final media i.e. a drop, a flat etc. 2. To determine the location and terminations of a wire, as with a "fox and hound" circuit tracer. 3. A feature, I believe exclusive to the ETC Eos/Ion, for editing multiple cues, similar to "track." 4. n - The copper conductors on a circuit board.