stencil vs tracing

stencil

noun
  • A two-ply master sheet for use with a mimeograph. 

  • A thin sheet, either perforated or using some other technique, with which a pattern may be produced upon a surface; a utensil that contains a perforated sheet. 

  • A pattern produced using such a utensil. 

verb
  • To print with a stencil. 

tracing

noun
  • A record in the form of a graph made by a device such as a seismograph. 

  • The process of finding something that is lost by studying evidence. 

  • A regular path or track; a course. 

  • The reproduction of an image made by copying it through translucent paper. 

How often have the words stencil and tracing occurred in a corpus of books? (source: Google Ngram Viewer )