plot vs undirected graph

plot

noun
  • A graph or diagram drawn by hand or produced by a mechanical or electronic device. 

  • An area or land used for building on or planting on. 

  • A plan; a purpose. 

  • Participation in any stratagem or conspiracy. 

  • Contrivance; deep reach thought; ability to plot or intrigue. 

  • Attractive physical attributes of characters involved in a story, originating from ironic juxtaposition with the original meaning (course of the story). 

  • A secret plan to achieve an end, the end or means usually being illegal or otherwise questionable. 

  • The course of a story, comprising a series of incidents which are gradually unfolded, sometimes by unexpected means. 

verb
  • To mark (a point on a graph, chart, etc). 

  • To conceive (a crime, misdeed etc). 

  • To trace out (a graph or diagram). 

undirected graph

noun
  • A graph in which the edges are not ordered, so the edge (a, b) is identical to the edge (b, a). 

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