plexus vs toils

plexus

noun
  • The system of equations required for the complete expression of the relations which exist between a set of quantities. 

  • A network of anastomosing or interwoven nerves, blood vessels, or lymphatic vessels. 

  • An interwoven combination of parts or elements in a structure or system. 

toils

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