third vs trisect

third

verb
  • To divide into three equal parts. 

  • To agree with a proposition or statement after it has already been seconded. 

noun
  • The person or thing in the third position. 

  • One of three equal parts of a whole. 

  • The third gear of a gearbox. 

  • third base 

  • A third-class degree, awarded to the lowest achievers in an honours degree programme 

  • An interval consisting of the first and third notes in a scale. 

  • A handicap of one stroke every third hole. 

adj
  • The ordinal form of the cardinal number three; Coming after the second. 

trisect

verb
  • to divide a quantity, angle etc into three equal parts 

  • to cut into three pieces 

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